Stop Lamps Circuit Test
WARNING: This page is about a different car, the 2006 Chevrolet Monte Carlo and 2006 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the brake pedal position sensor.
- Verify that a test lamp illuminates between the low reference circuit terminal C and B+.
- If the test lamp does not illuminate, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.
- If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- Ignition OFF, disconnect harness connector at the inoperative stop/turn lamp assembly.
- Ignition OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal G and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect a test lamp between the supply voltage circuit terminal A and ground.
- Ignition ON, command the appropriate LR or RR Turn Signal ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp is always ON, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- If the test lamp is always OFF, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, replace the inoperative stop/turn signal lamp assembly.