DTC Troubleshooting: P0504 (159)
  1. Check for continuity between ECM connector No. 2 terminal No. 36 and brake pedal position switch 4P connector terminal No. 3.
Is there continuity?
YES -
Go to Step 28 .
NO -
Repair open in the wire between the brake pedal position switch and ECM connector No. 2 terminal No. 36, then go to Step 29 .
  1. Check the brake pedal position switch.
Is the brake pedal position switch OK?
YES -
Go to Step 34 .
NO -
Adjust or replace the brake pedal position switch, then go to Step 29 .
  1. Turn the ignition switch OFF.
  1. Reconnect all connectors.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0504 indicated?
YES -
Check for poor connections or loose terminals at the brake pedal position switch and the ECM, then go to Step 1 .
NO -
Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■
  1. Reconnect all connectors.
  1. Update the ECM if it does not have the latest software, or substitute a known-good ECM.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0504 indicated?
YES -
Check for poor connections or loose terminals at the brake pedal position switch and the ECM. If the ECM was updated, substitute a known-good ECM, then recheck. If the ECM was substituted, go to Step 1 .
NO -
If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■