Service Information

Volt

Reading Lamps Malfunction

Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Reading Lamps B+	1, 2	1	--	--
Reading Lamps Ground Terminal 6	--	1	--	--
1. Reading Lamps Always OFF 2. Sun Visor Lamps Always OFF

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Reading Lamps B+

1, 2

Reading Lamps Ground Terminal 6

1. Reading Lamps Always OFF

2. Sun Visor Lamps Always OFF

Circuit/System Description

The body control module (BCM) supplies the dome/reading lamps and sun visor lamps with battery voltage. When switching on the following components the concerning lamps will illuminate:

•	Dome/reading lamps - row

•	Sun Visor - left Front

•	Sun Visor - right Front

Reference Information

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Vehicle in Service Mode, switch the dome/reading lamps or dome/reading lamps - row ON and OFF while observing the lamp. The concerning reading lamp should illuminate when switched ON.

Circuit/System Testing

Reading Lamps Circuit Malfunction

Vehicle OFF, disconnect the harness connector at the E37F Dome/Reading Lamps - Front.
Test for less than 5 Ω between the ground circuit terminal 6 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

Vehicle in Service Mode and dome/reading lamps OFF, test for greater than 11 V between the circuit terminal 1 and ground circuit terminal 6.
Vehicle in Service Mode and dome/reading lamps OFF, test for greater than 11 V between the circuit terminal 2 and ground circuit terminal 6.
Vehicle in Service Mode and dome/reading lamps OFF, test for greater than 11 V between the circuit terminal 3 and ground circuit terminal 6.
Vehicle in Service Mode and dome/reading lamps OFF, test for greater than 11 V between the circuit terminal 4 and ground circuit terminal 6.

⇒	If less than the specified range, test the circuits for a short to ground or an open/high resistance. If the circuits tests normal, replace the K9 Body Control Module.

If all circuits test normal, test or replace the E37F Dome/Reading Lamps - Front.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Reading Lamp Replacement

•	Dome and Reading Lamp Replacement

•	Control Module References for BCM replacement, programming and setup