Diagnostics and testing of headlight beam adjustment (Discovery 3)

Review

There are two headlight leveling systems: static and dynamic. Before performing diagnostics, check which headlight leveling system is installed on the vehicle.

Dynamic headlight levelling is only available for vehicles equipped with Adaptive Front-lighting System (AFS).

For a detailed description of the system design and operation, refer to Section 417-01 "Exterior Lighting" in the Service Station Manual.

Inspection and verification

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

2. Visually inspect for obvious electrical problems.

Mechanical factors

Electrical factors

Electric motor condition and installation (electric motors) and lever mechanism(mechanisms) headlight beam leveling correction Light switch and its installation Condition and installation of the left multifunction switch on the steering column

Fuses Battery electrical junction box (BJB) - fuse 11E Central electrical junction box (CJB) - fuse 61P CJB - fuse 56P CJB - fuse 27P CJB - fuse 62P Wiring harness Loosening or corrosion of connector(s) Battery Junction Box (BJB) Central Junction Box (CJB) Adaptive Front-lighting System (AFS) module Headlight Electric Drive Modules Engine Control Module (ECM) Anti-lock Brake System (ABS) Control Module Air suspension control unit LIN electrical circuits (Local interconnect network) 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 referring to the symptom chart or DTC index.

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

Clear all DTCs after troubleshooting.

Table of signs of malfunction

Sign of malfunction	Possible reasons	Actions
The headlight leveling system does not work	The fuse(s) have blown Tilt correction motor/linkage is faulty Malfunction of the headlight leveling adjustment circuit The air suspension system is faulty	Check the condition of the fuse(s) (see visual inspection table). Check the condition of the headlamp leveling motor and linkage. Check the headlamp leveling system electrical circuit. Refer to the electrical manual. Check for DTCs indicating a malfunction(s) in the headlamp leveling electrical circuit and the air suspension system.

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 codes	Description	Possible reasons	Actions
B1D3613	Turn signal switch	Left multifunction steering column switch: high resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system. Refer to the electrical guides and check the switch circuit. Replace/repair as necessary.
B1D4013	Electrical circuit for connecting the light switch	Light Switch Circuit: High Resistance	Refer to the guided diagnostic program for this code on the approved diagnostic system. Refer to the electrical guides and check the switch circuit. Replace/repair as necessary.
U018287	Lost Communication With Lighting Control Module - Front	CAN bus failure AFS module is disconnected AFS module not configured/calibrated AFS module failure	Refer to the "Network Communication" section in the service station manual.
U300016	Control module	The voltage in the electrical circuit is below the threshold value	Check the status and charging of the battery. See section 414-00 "Charging system" in the Service Station manual. Check the electrical circuits of the control module. Refer to the electrical equipment manual.
U300017	Control module	The voltage in the electrical circuit is above the threshold value	Check the status and charging of the battery. See section 414-00 "Charging system" in the Service Station manual. Check the electrical circuits of the control module. Refer to the electrical equipment manual.
U300042	Control module	General memory failure	If a module is suspected, refer to the Warranty Policy and Procedures Guide.
U300055	Control module	Incorrect software loaded CAN Wiring to AFS Module: High Resistance Incorrect CAN configuration for AFS module	Configure the modules using an approved diagnostic system. Check for CAN-related DTCs.
U1A1449	CAN initialization failure	Internal electronic malfunction	Check the power and ground circuits of the unit. Refer to the electrical manual. Configure the module(s) using the approved diagnostic system. If a module is suspect, refer to the warranty policy and procedures manual.