DTC P0504:00 [MZ-CD 1.6]
id0102g8155600
DTC P0504:00 |
Brake switch signal correlation |
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DETECTION CONDITION
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• The PCM monitors changes in the input signal for the brake switch signal (from instrument cluster). If the PCM detects a condition that either the brake switch signal is on or off for 200 s, the PCM determines that the brake switch signal have a compatibility malfunction.
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POSSIBLE CAUSE
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• Communication error between instrument cluster and PCM
• Brake switch malfunction
• Open or short circuit in wiring harness between brake switch and ground through brake light
• Open or short circuit in wiring harness between brake switch terminal D and PCM terminal 1U
• Open or short circuit in wiring harness between brake switch terminal C and instrument cluster terminal 2N
• Open circuit in wiring harness between brake switch terminal B and body ground
• Instrument cluster malfunction
• PCM malfunction
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Diagnostic procedure
STEP |
INSPECTION |
ACTION |
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1
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VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has the FREEZE FRAME DATA been recorded?
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Yes
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Go to the next step.
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No
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Record the FREEZE FRAME DATA on the repair order, then go to the next step.
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2
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VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related service repair information availability.
• Is any related repair information available?
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Yes
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Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
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No
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Go to the next step.
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3
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VERIFY STORED CAN COMMUNICATION DTC IN PCM AND INSTRUMENT CLUSTER
• Retrieve the PCM and instrument cluster DTC using the M-MDS.
• Is the CAN communication DTC present?
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Yes
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Go to the applicable DTC inspection.
(See DTC TABLE [MZ-CD 1.6].)
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No
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Go to the next step.
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4
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INSPECT BRAKE SWITCH CONNECTORS CONDITION
• Switch the ignition to off.
• Disconnect the brake switch connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
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Yes
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Repair or replace the connector and/or terminals, then go to Step 10.
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No
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Go to the next step.
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5
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VERIFY STOP LIGHT OPERATION
• Verify the stop light operation.
• Is the stop light turn on and off according to brake pedal conditions?
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Yes
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Go to Step 8.
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No
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Stop light is always on
• Repair or replace for a possible short to power supply between brake switch terminal D and PCM terminal 1U, then go to Step 10.
Stop light is always off, go to the next step.
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6
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VERIFY STOP FUSE CONDITION
• Verify the STOP fuse condition.
• Is the STOP fuse normal?
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Yes
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Go to the next step.
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No
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If the fuse is blown:
• Repair for short to ground in following wiring harness:
• If the fuse is deterioration:
Then go to Step 10.
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7
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VERIFY WHETHER MALFUNCTION IS BRAKE SWITCH OR OPEN CIRCUIT
• Inspect the brake switch.
(See BRAKE SWITCH INSPECTION.)
• Is there any malfunction?
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Yes
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Replace the brake switch, then go to Step 10.
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No
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Repair for a possible open circuit between brake switch terminal A and STOP fuse, then go to Step 10.
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8
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INSPECT BRAKE SWITCH SIGNAL CIRCUIT FOR OPEN
• Measure the voltage between PCM terminal 1U (wiring harness-side) and body ground.
• Is the voltage normal?
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Yes
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Go to the next step.
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No
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Repair for a possible open circuit between brake switch terminal D and PCM terminal 1U, then go to Step 10.
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9
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VERIFY WHETHER MALFUNCTION IS INSTRUMENT CLUSTER OR BRAKE SWITCH HARNESSES
• Measure the voltage between instrument cluster terminal 2N (wiring harness-side) and body ground.
• Is the voltage normal?
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Yes
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Replace the instrument cluster, then go to the next step.
(Instrument cluster can not transmit brake switch signal to PCM)
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No
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Repair for a possible open or short circuit between following, then go to the next step.
• Brake switch terminal C and instrument cluster terminal 2N
• Brake switch terminal B and body ground
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10
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VERIFY THAT DTC P0504:00 TROUBLESHOOTING IS COMPLETED
• Switch the ignition to ON.
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the M-MDS.
• Run the vehicle under the FREEZE FRAME DATA stored condition.
• Is the same DTC present?
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Yes
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Repeat the inspection from Step 1.
• If the malfunction recurs, replace the PCM.
Go to the next step.
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No
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Go to the next step.
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11
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VERIFY AFTER REPAIR PROCEDURE
• Perform the after repair procedure.
• Are any DTCs present?
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Yes
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Go to the applicable DTC inspection.
(See DTC TABLE [MZ-CD 1.6].)
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No
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DTC troubleshooting completed.
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