TSB : Circuit/System Testing

Details

Brake Pedal Position Sensor Malfunction Ignition OFF, disconnect the harness connector at the brake pedal position sensor. Ignition OFF, test for less than 5 Ω between the low reference circuit terminal C and ground. If greater than the specified range, 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 V between the 5 V reference circuit terminal A and ground. If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the BCM. Test for less than 0.3 V between the signal circuit terminal B and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM. Test for 4.8-5.2 V between the 5 V reference circuit terminal A and the signal circuit terminal B. If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM. If all circuits test normal, test or replace the brake pedal position sensor. Stop Lamp Malfunction Ignition OFF, disconnect the harness connector at the appropriate tail lamp. Test for less than 5.0 Ω between the ground circuit terminal listed below and ground: With RPO Z88 - terminal D Without RPO Z88 - terminal B If greater than the specified range, test the ground circuit for an open/high resistance. Connect a test lamp between the control circuit terminal listed below and ground: With RPO Z88 - terminal E Without RPO Z88 - terminal A Ignition ON, press and release the brake pedal. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If all circuits test normal, test or replace the tail lamp. Center High Mount Stop Lamp Malfunction Ignition OFF, disconnect the harness connector at the center high mounted stop lamp. Test for less than 5 Ω between the ground circuit terminal 1 and ground. If greater than the specified value, test the ground circuit for an open/high resistance. Connect a test lamp between the control circuit terminal 2 and ground. Ignition ON, press and release the brake pedal. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. If all circuits test normal, test or replace the center high mounted stop lamp.