Brake Switch Sense

Possible Causes

• Ground circuit open.
• Brake switch sense circuit open or shorted.
• Defective brake switch.
• Defective Powertrain Control Module (PCM).

1. Turn ignition off. Disconnect brake switch connector. Inspect connector. Clean or repair as necessary. Turn ignition on. Using scan tool in voltmeter mode, check voltage of brake switch sense circuit at brake switch connector terminal No. 1 (White/Pink wire). If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, go to step  3 .
2. Connect a jumper wire between brake switch connector terminals No. 1 (White/Pink wire) and No. 2 (Black wire). Using scan tool, read brake switch input status. If scan tool displays brake switch RELEASED, replace brake switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays brake switch PRESSED, repair open ground circuit. Perform TEST VER-4A  under VERIFICATION TESTS.
3. Turn ignition off. Disconnect PCM connectors. Inspect all connector terminals. If any terminal is damaged, pushed out or miswired, repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If terminals are okay, go to next step.
4. Using an ohmmeter, check resistance between ground and brake switch sense circuit (White/Pink wire) at PCM connector C3, terminal No. 24 (Cherokee) or C24 (Wrangler). If resistance less than 5 ohms, repair short to ground. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is 5 ohms or more, go to next step.
5. Using an ohmmeter, check resistance of brake switch sense circuit (White/Pink wire) between brake switch connector terminal No. 1 and PCM connector C3, terminal No. 24 (Cherokee) or C24 (Wrangler). If resistance is 5 ohms or more, repair open brake switch sense circuit. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-4A  under VERIFICATION TESTS.