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DTC P0504 [MZR-CD (RF Turbo)]

id0102f1832500

DTC P0504 | Brake switch circuit problem
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DETECTION CONDITION | • The PCM monitors changes in input voltage for brake switches No.1 and No.2. If the PCM detects that both brake switches No.1 and No.2 remain on or off for 3 s or there is a 0.5 s or more delay for each of the changes input voltage for brake switches No.1 and No.2, it determines that the brake switch circuit has a malfunction.
POSSIBLE CAUSE | • Brake switch malfunction • Open circuit between brake switch terminal A and PCM terminal 101 • Open circuit between brake switch terminal B and battery • Open circuit between brake switch terminal C and body ground • Open circuit between brake switch terminal D and PCM terminal 100 • Short to power between brake switch terminal A and PCM terminal 101 • Short to ground circuit between brake switch terminal D and PCM terminal 100 • Short to ground circuit between brake switch terminal A and PCM terminal 101 • PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded? | Yes | Go to the next step.
No | Record FREEZE FRAME DATA on the repair, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related service repair information availability. • Is any related repair information available? | Yes | Perform repair or diagnosis according to available repair information. • If vehicle is not repaired, go to the next step.
No | Go to the next step.
3 | INSPECT BRAKE SWITCH CONNECTOR FOR POOR CONNECTION • Turn the engine switch off. • Disconnect the brake switch connector. • Inspect for poor connection (such as damaged, pull-out pins, corrosion). • Is there any malfunction? | Yes | Repair or replace the terminal, then go to Step 10.
No | Go to the next step.
4 | INSPECT BRAKE SWITCH • Inspect the brake switch. (See BRAKE SWITCH INSPECTION.) • Is the brake switch normal? | Yes | Go to the next step.
No | Replace the brake switch, then go to Step 10. (See BRAKE PEDAL REMOVAL/INSTALLATION.)
5 | INSPECT GROUND CIRCUIT OF BRAKE SWITCH FOR OPEN CIRCUIT • Inspect for continuity between brake switch terminal C (wiring harness-side) and body ground. • Measure the voltage between brake switch terminal B (wiring harness-side) and body ground. • Is there continuity? | Yes | Go to the next step.
No | Repair or replace the wiring harness for open circuit, then go to Step 10.
6 | INSPECT SIGNAL CIRCUIT OF BRAKE SWITCH FOR SHORT TO GROUND • Inspect for continuity between the following terminals: - Brake switch terminal D (wiring harness-side) and body ground. - Brake switch terminal A (wiring harness-side) and body ground. • Is there continuity? | Yes | Repair or replace the wiring harness for short to ground circuit, then go to Step 10.
No | Go to the next step.
7 | INSPECT PCM CONNECTOR FOR POOR CONNECTION • Turn the engine switch off. • Disconnect the PCM connector. • Inspect for poor connection (such as damaged, pull-out pins, corrosion). • Is there any malfunction? | Yes | Repair or replace the terminal, then go to Step 10.
No | Go to the next step.
8 | INSPECT SIGNAL CIRCUIT OF BRAKE SWITCH FOR OPEN CIRCUIT • Inspect for continuity between the following terminals: - Brake switch terminal D (wiring harness-side) and PCM terminal 100 (wiring harness-side). - Brake switch terminal A (wiring harness-side) and PCM terminal 101 (wiring harness-side). • Is there continuity? | Yes | Go to the next step.
No | Repair or replace the wiring harness for open circuit, then go to Step 10.
9 | INSPECT SIGNAL CIRCUIT OF BRAKE SWITCH FOR SHORT TO POWER • Measure the voltage between brake switch terminal A (wiring harness-side) and body ground. • Is the voltage B+? | Yes | Repair or replace the wiring harness for short to power circuit, then go to the next step.
No | Go to the next step.
10 | VERIFY TROUBLESHOOTING OF P0504 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the WDS or equivalent. • Turn the engine switch to the ON position (Engine off). • Depress and release the brake pedal more than 5 times. • Is the same DTC present? | Yes | Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)
No | Go to the next step.
11 | VERIFY AFTER REPAIR PROCEDURE • Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE [MZR-CD (RF Turbo)].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [MZR-CD (RF Turbo)].)
No | Troubleshooting completed.