Test Description

WARNING: This page is about a different car, the 2004 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The number(s) below refer to the step number(s) on the diagnostic table.

2: Tests if a DTC B2578 is stored in the BCM. If both the LH and LH turn signal monitor DTCs are stored, test the hazard switch and related circuits for a short to battery positive voltage.
3: Tests if the BCM is receiving oscillating voltage on the LH turn signal monitor circuit. If the test lamp is ON steady, the BCM will set a DTC B2583.
4: Tests if the BCM is receiving oscillating voltage on the LH turn signal monitor circuit. If the test lamp is ON steady, the BCM will set a DTC B2583.
5: Tests if the turn signal switch or related circuits are shorted to battery positive voltage.
6: Tests if the hazard switch or related circuits are shorted to battery positive voltage.
7: Tests if the instrument panel cluster turn signal indicator is shorted to battery positive voltage.
8: Tests if the body control module is shorted to voltage.

DTC B2583

Step	Action	Yes	No
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Master Electrical Component List
1	Did you perform the Lighting System Diagnostic System Check?	Go to Step 2	Go to Diagnostic System Check - Lighting Systems
2	Install a scan tool. Turn ON the ignition, with the engine OFF. Select the BCM display DTC function on the scan tool. Does the scan tool display DTC B2583?	Go to Step 10	Go to Step 3
3	Turn OFF the ignition. Disconnect the LH DRL relay. Turn ON the ignition, with the engine OFF. Probe the LH turn signal monitor circuit at the LH DRL relay with a test lamp that is connected to ground. Refer to Power Distribution Schematics in Wiring Systems for electrical center circuit identification. Turn ON the LH turn signals. Does the test lamp turn ON and OFF with the LH turn signals?	Go to Step 13	Go to Step 4
4	Does the test lamp remain illuminated?	Go to Step 5	Go to Turn Signal Lamps and/or Indicators Inoperative
5	Disconnect the turn signal switch. Does the test lamp remain illuminated?	Go to Step 6	Go to Step 9
6	Disconnect the hazard switch. Does the test lamp remain illuminated?	Go to Step 7	Go to Step 10
7	Disconnect the instrument panel cluster. Does the test lamp remain illuminated?	Go to Step 8	Go to Step 11
8	Disconnect the body control module. Does the test lamp remain illuminated?	Go to Step 12	Go to Step 14
9	Repair a short to battery positive voltage in the turn signal switch circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 15	-
10	Repair a short to battery positive voltage in the hazard switch circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 15	-
11	Repair a short to battery positive voltage in the instrument panel turn signal indicator circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 15	-
12	Repair a short to battery positive voltage in the turn signal monitor circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 15	-
13	Replace the LH DRL relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems. Did you complete the replacement?	Go to Step 15	-
14	IMPORTANT: Perform the BCM reprogram procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Replace the BCM. Refer to Body Control Module Replacement in Body Control System.Did you complete the replacement?	Go to Step 15	-
15	Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Setting the DTC as specified in the supporting text. Does the DTC reset?	Go to Step 2	System OK