DTC P0703 [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed))

BME010200700W01

DTC P0703

Brake switch input malfunction

DETECTION CONDITION

• The PCM monitors changes in input voltage from the brake switch. If PCM does not detected the PCM terminal 82 voltage changes while alternately accelerating and deceleration 8 times the PCM determines that brake switch circuit has malfunction.
Diagnostic support note
• This is a continuous monitor (CCM).
• The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
• PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in PCM memory.

POSSIBLE CAUSE

• Brake switch malfunction
• Short to power harness between brake switch terminal B and PCM connector terminal 82.
• Open harness between brake switch terminal and PCM connector terminal 82.
• Open harness between battery positive terminal and brake switch terminal.
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

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 repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Check for related Service Information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT BRAKE SWITCH SIGNAL CIRCUIT FOR SHORT TO POWER
• Measure voltage between brake switch connector terminal B and body ground.
• Is voltage B+?
Yes
Repair or replace harness for short to power, then go to Step 9.
No
Go to Next step.
4
INSPECT BRAKE SWITCH CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect brake switch connector.
• Check for poor connection (damaged/pulled-out terminals, corrosion, etc.).
• Is there malfunction?
Yes
Repair or replace the terminal, then go to Step 9.
No
Go to the next step.
5
INSPECT BRAKE SWITCH POWER CIRCUIT FOR OPEN CIRCUIT
• Measure voltage between brake switch connector terminal A and body ground.
• Is voltage B+?
Yes
Go to the next step.
No
Repair or replace brake switch power circuit for open, then Go to Step 9.
6
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect PCM connector.
• Check for poor connection (damaged/pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair terminal, then go to Step 9.
No
Go to the next step.
7
INSPECT BRAKE SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Connect the PCM connector.
• Connect brake switch connector.
• Turn the ignition switch to the ON position (engine OFF).
• Depress brake pedal and measure voltage between PCM terminal 82 and body ground.
• Is voltage B+?
Yes
Go to the next step.
No
Repair or replace harness for open, then go to Step 9.
8
INSPECT BRAKE SWITCH
• Perform brake switch inspection.
• Is brake switch normal?
Yes
Go to the next step.
No
Replace brake switch, then go to the next step.
9
VERIFY TROUBLESHOOTING OF DTC P0703 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the memory using the WDS or equivalent.
• Drive vehicle 30 km/h {18.6 mph} or more.
• Depress and release brake pedal more than 10 times while driving vehicle.
• Is PENDING CODE for this DTC present?
Yes
Replace PCM, then go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.