Diagnostics and testing of the seat belt system (Discovery 3)

Safety information

CAUTION: To prevent accidental activation, de-energize the backup power source before performing any work on the SRS system or its components. Failure to follow this instruction may result in injury.

CAUTION: Do not use a multimeter to test the SRS module. There is a possibility that the meter battery will trigger the module. Failure to follow this instruction may result in personal injury.

NOTE: It is recommended that you do not use or have a cellular phone near you while working on the SRS system or its components.

Power outage

Before starting any work on the SRS system or related components:

1. Remove the ignition key.

2. Disconnect the battery cables, starting with the ground cable.

3. Wait 2 minutes for the main current circuit to discharge.

Complete instructions on proper SRS repair procedures are contained in the manual:

Inspection and verification

1. Check the validity of the customer's complaint.

2. Visually inspect for obvious mechanical and electrical problems.

(The full version is available on the website LRMAN.RU)

Mechanical elements	Electrical factors
Check for any non-standard optional equipment that may affect or interfere with the operation of the SRS system. Worn or damaged tape Locks/rods etc. Drums Sensor(s) Pretensioner(s)	Fuses Battery junction box (BJB) - 11E fuse Central junction box (CJB) - 9P fuse Central junction box (CJB) - 68P fuse. Wiring harness Control lamp(s) Crash sensor(s) Seat Belt Buckle Sensor(s) Pretensioner(s) Restraint Control Module (RCM)

3. If an obvious cause for the problem you identified or the customer described is found, correct it before proceeding with further actions. (if possible).



A faulty SRS wiring harness usually requires replacement of the harness in question. It is not recommended to repair the SRS wiring harness.

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

Clear all DTCs after troubleshooting.

Dynamic checks

Either of the following two procedures can be used to check that the seat belts are working properly. Both methods require two people, but remember that large people should not be used to perform these tests. This is to ensure that the complete unwinding of the seat belt webbing is not mistaken for proper locking by the seat belt retractor mechanism.

1st method of verification (braking)

• At a steady speed, the occupant should attempt to slowly pull the seat belt webbing out of each seat belt retractor in turn. Pulling the webbing out is not possible unless the vehicle motion-sensitive locking mechanism is working properly.
• Do not use any seat belt retractor mechanism that allows the belt to be pulled out during this check. A new seat belt must be installed.

Checking the seat belt sensor

With the vehicle stationary on a level, horizontal surface, firmly grasp the seat belt strap. (from the side of the tongue of the upper seat belt fastening element) and quickly pull the belt out. The retractor should lock at 0.25 meters, preventing further belt pulling. Do not use any seat belt retractor that allows the belt to be pulled out further. A new seat belt should be installed.

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
B005011	Driver seat belt sensor	Seat Belt Sensor Circuit Short to Ground	Check for DTCs for the steering wheel angle sensor. Check the seat belt buckle wiring for signs of damage. Refer to the electrical guide and check the seat belt sensor circuit. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B005015	Driver seat belt sensor	Seat Belt Sensor Circuit Short to Battery Voltage Seat Belt Sensor Circuit High Resistance	Check for DTCs for the steering wheel angle sensor. Check the seat belt buckle wiring for signs of damage. Refer to the electrical guide and check the seat belt sensor circuit. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B00501D	Driver seat belt sensor	Seat Belt Sensor Circuit Current Out of Operating Range	Check for DTCs for the steering wheel angle sensor. Check the seat belt buckle wiring for signs of damage. Refer to the electrical guide and check the seat belt sensor circuit. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B005064	Driver seat belt sensor	Seat Belt Sensor: No Signal Plausibility Possible Configuration Error (output is disabled but device is installed)	Check for DTCs for the steering wheel angle sensor. Check the seat belt buckle wiring for signs of damage. Refer to the electrical guides and check the seat belt sensor circuit. Configure the module using the approved diagnostic system. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B007011	Driver's seat belt pretensioner activation control	Trigger control circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B007012	Driver's seat belt pretensioner activation control	Electrical circuit for triggering: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B00701A	Driver's seat belt pretensioner activation control	Trip control circuit: resistance in circuit below threshold	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B00701B	Driver's seat belt pretensioner activation control	Trip control circuit: resistance in circuit above threshold	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B007064	Driver's seat belt pretensioner activation control	Trigger Control: No Signal Credibility	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B007211	Passenger seat belt pretensioner A activation control	Trigger control circuit: short circuit to ground	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B007212	Passenger seat belt pretensioner A activation control	Electrical circuit for triggering: short circuit to battery +	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B00721A	Passenger seat belt pretensioner A activation control	Trip control circuit: resistance in circuit below threshold	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B00721B	Passenger seat belt pretensioner A activation control	Trip control circuit: resistance in circuit above threshold	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B007264	Passenger seat belt pretensioner A activation control	Trigger Control: No Signal Credibility	Refer to the guided diagnostic program for this code on the approved diagnostic system.
B009011	Left front auxiliary restraint system sensor	Impact Sensor Circuit Short to Ground	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009012	Left front auxiliary restraint system sensor	Impact sensor electrical circuit: short circuit to battery +	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009064	Left front auxiliary restraint system sensor	Crash sensor: no signal plausibility Possible configuration error	Check the impact sensor and electrical circuits. Refer to the electrical guide. Configure the module using the approved diagnostic system.
B009081	Left front auxiliary restraint system sensor	Invalid serial data received. Possible high resistance.	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009092	Left front auxiliary restraint system sensor	Crash sensor: performance issues or malfunction	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009096	Left front auxiliary restraint system sensor	Crash sensor: internal component failure	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009511	Right front auxiliary restraint system sensor	Impact Sensor Circuit Short to Ground	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009512	Right front auxiliary restraint system sensor	Impact sensor electrical circuit: short circuit to battery +	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009564	Right front auxiliary restraint system sensor	Crash Sensor: No Signal Plausibility Possible Configuration Error (output is disabled but device is installed)	Check the impact sensor and electrical circuits. Refer to the electrical guide. Configure the module using the approved diagnostic system.
B009581	Right front auxiliary restraint system sensor	Invalid serial data received Possible high resistance	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009592	Right front auxiliary restraint system sensor	Crash sensor: performance issues or malfunction	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B009596	Right front auxiliary restraint system sensor	Crash sensor: internal component failure	Check the impact sensor and electrical circuits. Refer to the electrical manual.
B1A2595	Electric circuit of the driver's seat belt pre-tensioner electric igniter -short circuit to the ignition circuit	Pretensioner Igniter Circuit Short to Ignition + Pretensioner Igniter: Incorrect Assembly	Check the pretensioner igniter and electrical circuits. Refer to the electrical manual.
B1A2795	Electric circuit of the driver's seat belt pre-tensioner electric igniter -short circuit to the ignition circuit	Pretensioner Igniter Circuit Short to Ignition + Pretensioner Igniter: Incorrect Assembly	Check the pretensioner igniter and electrical circuits. Refer to the electrical manual.