DTC P2257 [13B-MSP]
id0102g1991700
DTC P2257 |
AIR pump relay control circuit low |
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DETECTION CONDITION
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• The PCM monitors the AIR pump relay control voltage when the AIR pump is not operating. If the control voltage is less than the specification, the PCM determines that the AIR pump relay control circuit voltage is low.
Diagnostic support note
• This is a continuous monitor (AIR system).
• 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.
• The DTC is stored in the PCM memory.
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POSSIBLE CAUSE
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• Connector or terminal malfunction
• Open circuit in wiring harness between main relay terminal C and AIR pump relay terminal D
• Short to ground in wiring harness between main relay terminal C and AIR pump relay terminal D
• Short to ground in wiring harness between AIR pump relay terminal A and PCM terminal 1G
• AIR pump relay malfunction
• Open circuit in wiring harness between AIR pump relay terminal A and PCM terminal 1G
• PCM malfunction
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Diagnostic procedure
STEP |
INSPECTION |
ACTION |
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1
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VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED
• Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (AIR system related) 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 and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
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2
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VERIFY RELATED SERVICE INFORMATION AVAILBAILITY
• Verify related Service information availability.
• Is any related Service information available?
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Yes
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Perform repair or diagnosis according to thavailable Service 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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INSPECT AIR PUMP RELAY CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect the AIR pump relay 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 terminal, then go to Step 9.
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No
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Go to the next step.
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4
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INSPECT AIR PUMP RELAY POWER CIRCUIT FOR OPEN CIRCUIT OR SHORT TO GROUND
• Turn the ignition switch to the ON position (engine off).
• Measure the voltage between AIR pump relay terminal D (wiring harness-side) and body ground.
• Is the voltage B+?
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Yes
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Go to the next step.
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No
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Repair or replace the wiring harness for a possible open circuit or short to ground, then go to Step 9.
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5
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INSPECT AIR PUMP RELAY CONTROL CIRCUIT FOR SHORT TO GROUND
• Turn the ignition switch off.
• Inspect for continuity between AIR pump relay terminal A (wiring harness-side) and body ground.
• Is there continuity?
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Yes
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Repair or replace the wiring harness for a possible short to ground, then go to Step 9.
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No
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Go to the next step.
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6
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INSPECT AIR PUMP RELAY
• Inspect the AIR pump relay.
(See RELAY INSPECTION.)
• Is there any malfunction?
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Yes
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Replace the AIR pump relay, then go to Step 9.
(See RELAY LOCATION.)
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No
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Go to the next step.
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7
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INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect the PCM 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 terminal, then go to Step 9.
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No
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Go to the next step.
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8
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INSPECT AIR PUMP RELAY CONTROL CIRCUIT FOR OPEN CIRCUIT
• Turn the ignition switch off.
• Inspect for continuity between AIR pump relay terminal A (wiring harness-side) and PCM terminal 1G (wiring harness-side).
• Is there continuity?
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Yes
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Go to the next step.
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No
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Repair or replace the wiring harness for a possible open circuit, then go to the next step.
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9
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VERIFY TROUBLESHOOTING OF DTC P2257 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the M-MDS.
• Start the engine.
• Is the PENDING CODE same as DTC present?
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Yes
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Replace the PCM, then go to the next step.
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No
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Go to the next step.
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10
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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 [13B-MSP].)
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No
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DTC troubleshooting completed.
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