Diagnostics and testing of automatic transmission 4.0L (Discovery 3)

Review

This section is intended to provide mechanics with a description of methods for diagnosing transmission component failures rather than replacing the entire unit.

However, there are a number of situations where replacement of the unit is the only practical solution, and this section will cover the diagnostics required to gather the information required for transmission replacement to be approved under the Warranty Prior Approval Program (WPAP) where applicable, and will also reveal any diagnostic trouble codes (DTCs) stored by the control module.

Basic checks of the transmission should be performed first. (condition and level of liquid, etc.), and for this it is necessary to use an approved diagnostic system or other equipment with the ability to record data for temperature monitoring, etc.

Information on the operation of the gearbox can be found in the relevant section of the service manual.

Inspection and verification

1. Ensure that the customer's complaint is justified.

2. Visually inspect for obvious mechanical and electrical problems.

Mechanical factors	Electrical factors
Liquid state Liquid level Brake fluid leaks Working fluid heat exchanger External lever mechanisms Gear selector lever	Fuses and fuses Wiring harnesses Electrical connector(s) Transmission Control Module (TCM) Engine Control Module (ECM) CAN electrical circuits (Control Area Network)

3. If an obvious cause for the problem you identified or the customer described is found, resolve it before moving on to further action. (if possible).



4. Use the approved diagnostic system or scan tool to retrieve all diagnostic trouble codes (DTCs) before accessing the DTC Index.

Since DTCs are stored in more than one module, a full vehicle data read is recommended.

Clear all DTCs after troubleshooting.

Preliminary inspection

1. Ask the owner/driver as much information about the fault as possible to facilitate diagnosis. Taking the time to do this will reduce the need for an extensive road test and the likelihood of possible missed diagnostics.

The information required by WPAP is still useful as an aid in performing diagnostics, even when the system is not in operation.

Required information for WPAP (if applicable)

• Nature of the malfunction (loss of transmission, slippage, intense vibration, gear shift quality, noise, etc.)
• The frequency with which the fault occurs
• Conditions under which the fault occurs, including temperature (coolant and external), the selected gear, the vehicle speed, the engine speed and any specific conditions
• Before continuing with transmission diagnostics, check for non-transmission related DTCs and perform any necessary actions.

2. Record detailed information about the vehicle, including:

• Service Information
• Gearbox serial number
• Gearbox software option

3. Visually inspect the transmission for transmission fluid leaks, damage, etc.

4. Check the condition of the transmission fluid.

NOTE: The condition of the transmission fluid is a good indicator of the internal condition of the transmission. If the fluid shows signs of overheating and/or is contaminated, this usually indicates that the internal damage to the transmission is such that the best course of action is to replace the unit. Compare the color and odor of the fluid drained from the transmission with fresh fluid.

5. Check the transmission fluid level. Refer to the appropriate section in the service manual.

NOTE: This is important for the operation of the transmission and it is necessary to follow the procedure exactly to avoid any inaccuracies in the diagnosis, with the resulting possible issuance of a warranty claim.

6. Check the idle speed and throttle position sensor using the approved diagnostic system or scan tool.

7. Check the gear selector cable adjustment. Refer to the relevant section in the workshop manual.

(The original article is located on the website: LRMAN.ru)

8. Check the adjustment of the transmission range sensor.

A comprehensive transmission range sensor adjustment procedure is available using the approved diagnostic system.

If any faults are found and then corrected in the above sequence, clear all DTCs and check the vehicle for proper operation.

If a fault is found that indicates a transmission replacement is required, a request must be made under the Warranty Pre-Approval Program before work begins. (if applicable).

DTC Index

NOTE: Generic scan tools cannot read the codes listed or can only read 5-digit codes. Match the 5 digits from the scan tool with the first 5 digits of the listed 7-digit code to identify the fault. (the last 2 digits provide additional information readable by a manufacturer approved diagnostic system).

DTC	Description	Possible reasons	Action
P012100	Problems with the operating range/ electrical circuit characteristics of the throttle position sensor A/ accelerator pedal	Throttle Position Sensor Wiring: High Resistance Throttle Position Sensor Signal Circuits (throttle position 1 or throttle position 2): short circuit to battery + Throttle position sensor malfunction Kickdown Range/Characteristics Issues with Partial Accelerator Pedal Depression	Check for DTCs related to the pedal position sensor. Configure the module using the approved diagnostic system.
P021900	Engine crankshaft overspeed condition	Uncharacteristic engine speed	Check for engine management related DTCs.
P050000	Vehicle Speed Sensor A	Vehicle speed signal not registered	Check for DTC codes for ABS Check the CAN electrical circuits. Refer to the electrical equipment manual.
P050100	Vehicle Speed Sensor A Range/Performance Problems	Operating range/performance issues	Check for DTC codes related to the primary / secondary shaft sensor. Check the CAN electrical circuits. Refer to the electrical equipment manual.
P056100	Unstable voltage in the system	Supply voltage outside operating range with engine running	Check the battery and charging system. Refer to the relevant section in the service station manual.
P056200	Low voltage in the system	Very low supply voltage to TCM	Check battery condition and charge. Check TCM power supply circuits. Refer to electrical manual.
P056300	High voltage in the system	The supply voltage is too high with the engine running and jump starting was not performed and the gearbox was not in emergency mode	Check the battery and charging system. Refer to the relevant section in the service station manual. Check if the vehicle has been jump-started using jumper cables.
P060100	Internal control module memory checksum error	Checksum error	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P060300	Internal Control Module Persistent Memory (KAM) Error	Persistent Memory (KAM) Error	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P060500	Internal Control Module Read Only Memory (ROM) Error	Read-Only Memory (ROM) Error	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P061300	TCM processor	CPU	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P062F00	Internal Control Module EEPROM Error	EEPROM error	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P064200	Low Reference Voltage in Sensor Circuit A	Reference voltage circuit: short circuit to ground Reference voltage circuit: high resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P064300	High Reference Voltage in Sensor Circuit A	Reference voltage circuit: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P065700	Open circuit of the supply voltage A of the actuator	Power supply voltage circuit: high resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P065800	Low voltage in the electric circuit of the supply voltage A of the actuator	Electrical supply voltage circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P065900	High voltage in the electric circuit of the supply voltage A of the actuator	Electrical supply voltage circuit: short circuit to + battery	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P066800	PCM/ECM/TCM Internal Temperature Sensor A Circuit Low Voltage	Temperature sensor circuit: high resistance Temperature sensor electrical circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P066900	PCM/ECM/TCM Internal Temperature Sensor A Circuit High Voltage	Temperature sensor electrical circuit: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P070500	Transmission Range Sensor A Circuit (input signal PRNDl)	Unusual signal	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P071000	Transmission Fluid Temperature Sensor A Circuit	Temperature rise rate too low	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P071100	Transmission Fluid Temperature Sensor A Circuit Range/Performance Problem	Sensor electrical circuits: short circuit to each other	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P071200	Low Voltage in Transmission Fluid Temperature Sensor A Circuit	Sensor circuit: high resistance Sensor electrical circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P071300	Transmission Fluid Temperature Sensor A Circuit High Voltage	Sensor electrical circuit: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P071600	Turbine/Input Shaft Speed Sensor A Circuit Range/Performance Problem	Sensor circuit: high resistance Sensor electrical circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P071700	No signal in the electrical circuit of the turbine/input shaft speed sensor A	Sensor electrical circuit: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P072000	Output shaft speed sensor electrical circuit	Sensor electrical circuit: short circuit to battery + Sensor circuit: high resistance Sensor electrical circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P072122	Output Shaft Speed Sensor Circuit Range/Performance Problems	Range/Characteristics Issues Signal Amplitude	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P072127	Output Shaft Speed Sensor Circuit Range/Performance Problems	Operating range/performance issues The rate of change of the signal is above the threshold value	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P072164	Output Shaft Speed Sensor Circuit Range/Performance Problems	Operating range/performance issues Lack of signal credibility	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P072900	Incorrect gear ratio for gear 6	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073000	Incorrect gear ratio	Too much slip between the primary and secondary shaft speeds	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073100	Incorrect gear ratio for gear 1	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073200	Incorrect gear ratio for gear 2	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073300	Incorrect gear ratio for gear 3	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073400	Incorrect gear ratio for gear 4	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073500	Incorrect gear ratio for gear 5	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P073600	Incorrect reverse gear ratio	Incorrect gear ratio Too much slip between the speed values of the input and output shafts	Check for speed sensor related DTCs Check sensor circuits Refer to electrical manual.
P074000	Open circuit of the electromagnetic valve of the torque converter clutch	Solenoid valve circuit: high resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P074100	Performance issues/stuck in off position of torque converter clutch solenoid valve electrical circuit	Solenoid valve electrical circuit: stuck in off position	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P074800	Electrical fault in pressure control solenoid valve A	Solenoid valve current too high/low	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P075113	Performance issues/shift solenoid valve A stuck in off position	Problems with characteristics Jamming in off state Solenoid valve circuit: high resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P075114	Performance issues/shift solenoid valve A stuck in off position	Problems with characteristics Jamming in off state Solenoid valve circuit: high resistance Solenoid valve electrical circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P075200	Shift Solenoid Valve A Stuck in On Position	Stuck in on state	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P075300	Electrical fault in shift solenoid valve A	Solenoid valve electrical circuit: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P077800	Electrical fault in pressure control solenoid valve B	Solenoid valve current too high	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P078000	Gear shift malfunction	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078123	Switch 1-2	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not disengage	Check fluid level and condition. Check for related DTCs.
P078162	Switch 1-2	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078164	Switch 1-2	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078262	Switch 2-3	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078264	Switch 2-3	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078323	3-4 switch	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not disengage	Check fluid level and condition. Check for related DTCs.
P078362	3-4 switch	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078364	3-4 switch	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078423	4-5 switch	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not disengage	Check fluid level and condition. Check for related DTCs.
P078462	4-5 switch	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P078464	4-5 switch	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P079800	Electrical fault in pressure control solenoid valve C	Solenoid valve current too high	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P081C00	Parking Position Input Signal Circuit	Parking Position Lock Signal Failure	Check the gear selector input circuits. Refer to the electrical manual.
P082600	Upshift and downshift electrical circuit	Invalid signal	Check the upshift and downshift electrical circuits. Refer to the electrical manual.
P082923	Switch 5-6	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not disengage	Check fluid level and condition. Check for related DTCs.
P082962	Switch 5-6	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P082964	Switch 5-6	Too high ratio between primary and secondary shaft speeds during gear shifting. Clutch does not open or close	Check fluid level and condition. Check for related DTCs.
P085000	Park/Neutral Position Sensor Switch Input Circuit	Starter Lock Signal Failure	Check the starter interlock circuits. Refer to the electrical manual.
P089700	Deterioration of transmission fluid	Too high temperature for too long a period of time	Replace the fluid.
P092800	Open circuit of the A solenoid/actuator of the gear shift lock	Solenoid valve circuit: high resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P092900	Problems with the operating range / characteristics of the electrical circuit A of the electromagnet / gear lock actuator	Solenoid valve electrical circuit: short circuit to ground Solenoid valve circuit: high resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P093000	Low voltage in the electrical circuit A of the electromagnet / gearshift interlock actuator	Solenoid valve electrical circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P093100	High voltage in the electrical circuit A of the electromagnet / gearshift interlock actuator	Solenoid valve electrical circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P093800	Hydraulic Fluid Temperature Sensor Range/Performance Problems	Range/Characteristics Issues Signal is not typical	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P096013	Open circuit in the control circuit of the electromagnetic pressure control valve A	Control circuit: high resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system.
P096014	Open circuit in the control circuit of the electromagnetic pressure control valve A	Control circuit: high resistance Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096200	Low voltage in the control circuit of the pressure control solenoid valve A	Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096300	High voltage in the electrical circuit of the pressure control solenoid valve A	Control circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096413	Open circuit in the control circuit of the electromagnetic valve of pressure control B	Control circuit: high resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096414	Open circuit in the control circuit of the electromagnetic valve of pressure control B	Control circuit: high resistance Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096600	Low voltage in the electrical circuit of the solenoid valve of pressure control B	Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096700	High voltage in the electrical circuit of the solenoid valve of pressure control B	Control circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096813	Open circuit in the control circuit of the electromagnetic pressure control valve C	Control circuit: high resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P096814	Open circuit in the control circuit of the electromagnetic pressure control valve C	Control circuit: high resistance Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P097000	Low voltage in the control circuit of the solenoid valve of pressure control C	Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P097100	High voltage in the electrical circuit of the solenoid valve of pressure control C	Control circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P178300	Gearbox overheating condition	Valve Block Module Shutdown Detected in Last Driving Cycle	Check fluid level and condition. Check for related DTCs.
P271600	Electrical fault in pressure control solenoid valve D	Solenoid valve current too high	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P271813	Open circuit in the control circuit of the pressure control solenoid valve D	Control circuit: high resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P271814	Open circuit in the control circuit of the pressure control solenoid valve D	Control circuit: high resistance Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P272000	Low voltage in the control circuit of the pressure control solenoid valve D	Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P272100	High voltage in the electrical circuit of the pressure control solenoid valve D	Control circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P272500	Electrical fault in pressure control solenoid valve E	Solenoid valve current too high	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P272713	Open circuit of the control circuit of the electromagnetic pressure control valve E	Control circuit: high resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P272714	Open circuit of the control circuit of the electromagnetic pressure control valve E	Control circuit: high resistance Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P272900	Low voltage in the control circuit of the solenoid valve pressure control E	Electrical control circuit: short circuit to ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P273000	High voltage in the control circuit of the solenoid valve pressure control E	Control circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P275900	Electrical fault in torque converter clutch pressure control solenoid valve	Pressure control solenoid valve malfunction	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P276100	Open circuit in the electrical control circuit of the electromagnetic valve for controlling the pressure of the torque converter clutch	Pressure Control Solenoid Valve Circuit High Resistance	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P276200	Torque Converter Clutch Pressure Control Solenoid Control Circuit Range/Performance Problems	Pressure control solenoid valve electrical circuit: current too low	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P276300	High voltage in the electrical circuit of the solenoid valve of pressure control of the torque converter clutch	Pressure control solenoid valve electrical circuit: short circuit to battery +	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
P276400	Low voltage in the electrical circuit of the solenoid valve of pressure control of the torque converter clutch	Pressure Control Solenoid Valve Circuit Short to Ground	Check the solenoid valve electrical circuits. Refer to the electrical equipment manual.
U000188	High-speed CAN data bus	The bus is disconnected	The module generating this code has disabled CAN bus communication. Check for other CAN bus disable codes. Check module and circuits. Refer to the electrical manual. If a module is suspected, refer to the warranty policy and procedures manual.
U010087	Lost Communication with ECM/PCM "A"	No message	Check ECM and electrical circuits. Refer to electrical manual.
U010287	Lost Communication with Transfer Case Control Module	No message	Check the transfer case control module and electrical circuits. Refer to the electrical manual.
U010487	Lost Communication with Cruise Control Module	No message	Check the cruise control module and electrical circuits. Refer to the electrical manual.
U012287	Lost Communication with Vehicle Dynamics Control Module	No message	Check the ABS module and electrical circuits. Refer to the electrical manual.
U012687	Lost Communication with Steering Angle Sensor Module	No message	Check the steering angle sensor and electrical circuits. Refer to the electrical manual.
U012887	Lost Communication With Parking Brake Control Module	No message	Check the parking brake control module and electrical circuits. Refer to the electrical manual.
U013887	Lost Communication with Terrain Response System Control Module	No message	Check the terrain response control module and electrical circuits. Refer to the electrical manual.
U015587	Lost Communication with Instrument Panel Control (IPC) Module	No message	Check the instrument cluster and electrical circuits. Refer to the electrical equipment manual.
U030055	Internal control module software incompatibility	The module configuration is not configured	Configure the module using an approved diagnostic system.
U040186	Invalid data received from ECM/PCM A	Invalid signal	Check engine speed on instrument cluster. Check for DTCs in ECM.
U041686	Invalid data received from vehicle dynamics control module	Invalid signal	Check for ABS DTCs
U30004A	Control module	Invalid element installed Mismatch between configuration data and read configuration	Configure the module using an approved diagnostic system.