DESCRIPTION
Lighting system data can be read from the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the GTS to check for malfunctions and perform repairs.
CHECK DLC3
Check the DLC3.
INSPECT AUXILIARY BATTERY VOLTAGE
Measure the auxiliary battery voltage.
If the voltage is below 11 V, recharge or replace the auxiliary battery.