DTC P0703: Brake Switch Sense Circuit: Testing
- Turn ignition off. Disconnect brakelight switch harness connector located above brake pedal. Measure resistance between ground and brakelight switch ground circuit (Black wire) at brakelight switch harness connector terminal No. 5. See Fig 1
. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in brakelight switch ground circuit.
- Turn ignition off. Disconnect PCM harness connectors. See Figure
. Measure resistance of brake switch sense circuit (White/Pink wire) between brakelight switch harness connector terminal No. 6 and terminal No. 62 at PCM C2 harness connector. See Figure
. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in brake switch sense circuit.
- Measure resistance between brakelight switch terminals No. 5 and 6 (component side). With brake pedal released, resistance should be less than 5 ohms. With brake pedal applied, resistance should be infinite. If resistance is as specified, go to next step. If resistance is not as specified, replace brakelight switch.
- Measure resistance between ground and brake switch sense circuit (White/Pink wire) at brakelight switch harness connector terminal No. 6. If resistance is more than 100 k/ohms, go to next step. If resistance is 100 k/ohms or less, repair short to ground in brake switch sense circuit.
- If no other possible causes are remaining, replace PCM.
Courtesy of DAIMLERCHRYSLER CORPORATION