Stop Lamps Always On Pickup
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
DEFINITION: This diagnostic is only to be performed when the rear stoplamps remain illuminated at all times. | ||||
1 | Was the Exterior Lights System Check performed? | -- | Go to Step 2 | |
2 | Remove the Brake Lamp Relay. Do the brake lights go out? | -- | Go to Step 3 | Go to Step 8 |
3 | Measure voltage at D& of the Brake Lamp Relay Connector. Was voltage present? | V | Go to Step 4 | Go to Step 5 |
4 | Disconnnect the Stoplamp, TCC, and Cruise Control Switch Connector. Is voltage still present at D7 of the Brake Lamp Relay Connector? | V | Go to Step 6 | Go to Step 7 |
5 | Replace the Brake Lamp Relay. Is the repair complete? | -- | -- | |
6 | Repair the short to voltage in CKT 17 (WHT). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
7 | Replace the Stoplamp, TCC, and Cruise Control Switch. Is the repair complete? | -- | -- | |
8 | Repair the short to voltage in CKT 20 (LT BLU). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
Stop Lamps Always On Suburban/Utility
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
DEFINITION: This diagnostic procedure should only be used when the rear stop lamps both stay illuminated at all times. | ||||
1 | Was the Exterior Lights System Check performed? | -- | Go to Step 2 | |
2 | Disconnect the Stop, TCC, and Cruise Control Switch. Do the lamps turn off? | -- | Go to Step 3 | Go to Step 4 |
3 | Replace the Stop, TCC, and Cruise Control Switch. Is the repair complete? | -- | -- | |
4 | Disconnect the Directional Signal Switch. Do the lamps turn off? | -- | Go to Step 5 | Go to Step 8 |
5 | Measure voltage at pin A1 of the Directional Signal Switch. Is voltage present? | -- | Go to Step 6 | Go to Step 8 |
6 | Repair the short to voltage on CKT 17 (WHT). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
7 | Replace the Directional Signal Switch. Is the repair complete? | -- | -- | |
8 | Repair the short to voltage on CKT 18 (YEL) and CKT 19 (DK GRN). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
