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 DTC P0482 [L8, LF]

DTC P0482 [L8, LF]

id0102a18078b1

DTC P0482

Cooling fan relay No.4 control circuit malfunction

DETECTION CONDITION

• PCM monitors cooling fan relay No.4 control signal. If voltage remains low or high, PCM determines that fan relay circuit has a malfunction.
Diagnostic support note
• This is a continuous monitor (Other).
• MIL does not illuminate.
• PENDING CODE is available if PCM detects the above malfunction condition.
• FREEZE FRAME DATA is not available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Cooling fan relay No.4 malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between ignition switch and cooling fan relay No.4 terminal E
• Open circuit in wiring harness between cooling fan relay No.4 terminal A and PCM terminal 1N
• Short to ground in wiring harness between cooling fan relay No.4 terminal A and PCM terminal 1N
• Short to power supply in wiring between cooling fan relay No.4 terminal A and PCM terminal 1N
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT COOLING FUN RELAY NO.4 CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect cooling fan relay No.4 connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal and/or connector, then go to Step 10.
No
Go to the next step.
4
INSPECT COOLING FUN RELAY NO.4 POWER CIRCUIT FOR OPEN CIRCUIT
• Turn ignition switch to ON (Engine off).
• Measure voltage between cooling fan relay No.4 terminal E (harness-side) and body ground.
• Is voltage B+?
Yes
Go to the next step.
No
Replace or replace the wiring harness for an open circuit, then go to Step 10.
5
INSPECT COOLING FUN RELAY NO.4
• Inspect cooling fan relay No.4.
• Is cooling fan relay No.4 normal?
Yes
Go to the next step.
No
Replace the cooling fan relay No.4, then go to Step 10.
6
INSPECT COOLING FUN RELAY NO.4 CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY
• Measure voltage between cooling fan relay No.4 terminal A (harness-side) and body ground.
• Is voltage B+?
Yes
Repair or replace the wiring harness for short to power supply, then go to Step 10.
No
Go to the next step.
7
INSPECT COOLING FUN RELAY NO.4 CONTROL CIRCUIT FOR SHORT TO GROUND
• inspect for continuity between cooling fan relay No.4 terminal A (harness-side) and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness for an open circuit, then go to Step 10.
No
Go to the next step.
8
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal and/or connector, then go to Step 10.
No
Go to the next step.
9
INSPECT COOLING FUN RELAY NO.4 CONTROL CIRCUIT FOR OPEN CIRCUIT
• inspect for continuity between cooling fan relay No.4 terminal A (harness-side) and PCM terminal 1N (harness-side).
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for an open circuit, then go to the next step.
10
VERIFY TROUBLESHOOTING OF DTC P0482 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Perform the KOEO or KOER self-test.
• Is the DTC P0481 present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
11
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Is any DTC present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.