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 DTC B1483, B1484, B1486 [DSC]

DTC B1483, B1484, B1486 [DSC]

id040220874700

DTC

B1483, B1484, B1486

Brake switch signal

DETECTION CONDITION

• B1483
- A signal error is input for 5 s or more from the brake switch.
• B1484
- The brake switch on signal is input continuously for 120 s or more under the specified driving conditions.
• B1486
- The brake switch off signal is input continuously for 150 s or more even with 1.5 MPa or more of brake fluid pressure.

POSSIBLE CAUSE

• B1483
- Malfunction of brake switch
• B1484
- Short to power circuit in wiring harness between the brake switch and PCM terminal
• B1486
- Short to ground circuit in wiring harness between the brake switch and PCM terminal
- Open circuit in wiring harness between the brake switch and PCM terminal

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY OPEN OR SHORT CIRCUIT IN BRAKE SWITCH SIGNAL
• Turn the ignition switch to the ON position.
• Measure the voltage between the following PCM connector terminals and body ground when the brake pedal is depressed and released.
- PCM (L8, LF, L3): 1AB
- PCM (L3 Turbo): 1K
- PCM (MZR-CD (RF Turbo)): 100

Voltage

Brake pedal depressed: B+

Brake pedal released:

1 V or less

Yes
Go to Step 5.
No
If it is B+ under any condition, then go to the next step.
If it is 1 V or less under any condition, then go to Step 3.
2
INSPECT BRAKE SWITCH SIGNAL FOR SHORT TO POWER SUPPLY CIRCUIT
• Disconnect the brake switch connector.
• Measure the voltage between the brake switch connector terminal D (vehicle harness-side) and body ground.
• Is the voltage 1 V or less?
Yes
Go to Step 4.
No
Repair or replace the wiring harness between the PCM and brake switch, then go to Step 5.
3
INSPECT BRAKE SWITCH SIGNAL FOR OPEN CIRCUIT
• Disconnect the PCM connectors.
• Disconnect the brake switch connector.
• Inspect continuity between the following PCM connector terminals (vehicle harness-side) and brake switch terminal D.
- PCM (L8, LF, L3, L3 Turbo): 1AB
- PCM (L3 Turbo): 1K
- PCM (MZR-CD (RF Turbo)): 100
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness between the PCM and brake switch, then go to Step 5.
4
INSPECT BRAKE SWITCH
• Inspect the brake switch.
• Is the brake switch normal?
Yes
Go to the next step.
No
Replace the brake switch, then go to the next step.
5
VERIFY THAT THE SAME DTC IS NOT PRESENT
• Reconnect all disconnected connectors.
• Clear the DTCs from the memory.
• Are the same DTCs present?
Yes
Repeat the inspection from Step 1.
If the malfunction recurs, replace the DSC HU/CM, then go to the next step.
No
Go to the next step.
6
VERIFY THAT NO OTHER DTCS ARE PRESENT
• Are any other DTCs output?
Yes
Go to the applicable DTC inspection.
(See DTC Table.)
No
DTC troubleshooting completed.