DTC P0505

BHE010200500W02

DTC P0505

Idle air control system problem

DETECTION CONDITION

• The PCM cannot control idle speed at the target idle speed during the self-test.

Diagnostic support note

• The MIL does not illuminate.
• PENDING CODE is not available.
• FREEZE FRAME DATA is not available.
• The DTC is not stored in the PCM memory.

POSSIBLE CAUSE

• Drive-by-wire control system malfunction
• A/C cut-off control malfunction
• Generator control system malfunction
• Intake-air line clogged
– Air cleaner clogged
– Throttle body clogged
• Insufficient compression
– Engine oil malfunction
– Oil pressure decrease
– Metering oil pump malfunction
– Metering oil pump control malfunction
– Engine malfunction
• Fuel line pressure malfunction
• 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 the FREEZE FRAME DATA on the repair order, then go to the next step.
2

VERIFY RELATED REPAIR INFORMATION AVAILABILITY

• Verify related service repair 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

VERIFY RELATED PENDING CODE OR STORED DTC

• Turn the ignition switch off, then to the ON position (Engine off).
• Verify the related PENDING CODE or stored DTCs.
• Are other DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE.)
No
Go to the next step.
4

INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION

• Perform the "Drive-by-wire Control System Inspection".
• Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
Then go to Step 15.
No
Go to the next step.
5

INSPECT A/C MAGNETIC CLUTCH OPERATION

Note
• The following test should be performed for A/C. Go to the next step for vehicles without A/C.
• Turn the blower motor switch off.
• Is magnetic clutch still on?
Yes
Go to the "NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY.".
No
Go to the next step.
6

INSPECT GENERATOR CONTROL SYSTEM OPERATION

• Apply the electrical load at idle.
• Is the engine speed increased?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible short to power supply, then go to Step 9.
7

INSPECT AIR CLEANER ELEMENT

• Remove the air cleaner element with engine running.
• Is the engine speed increased?
Yes
Clean or replace the air cleaner element, then go to Step 14.
No
Go to the next step.
8

INSPECT THROTTLE BODY PASSAGE

• Remove the throttle body.
• Is throttle body clogged?
Yes
Clean the throttle body passage or replace the throttle body, then go to Step 14.
No
Go to the next step.
9

INSPECT ENGINE COMPRESSION

• Inspect the engine compression.
• Is there any malfunction?
Yes
Go to the next step.
No
Go to Step 14.
10

INSPECT METERING OIL PUMP

• Inspect the metering oil pump.
• Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
Overhaul or replace the engine.
Then go to Step 15.
No
Go to the next step.
11

INSPECT ENGINE OIL CONDITION

• Inspect the engine oil condition.
• Is the engine oil condition normal?
Yes
Go to the next step.
No
Replace the engine oil.
Inspect the ECT sensor and related harnesses.
Overhaul or replace the engine.
Then go to Step 15.
12

INSPECT OIL PRESSURE

• Inspect the oil pressure.
• Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
Overhaul or replace the engine.
Then go to Step 15.
No
Go to the next step.
13

INSPECT OIL PASSAGE

• Inspect the oil pipe between metering oil pump and metering oil nozzle.
• Is there any malfunction?
Yes
Inspect and repair for leakage and/or clogged in oil passage at engine.
Overhaul or replace the engine.
Then go to Step 15.
No
Overhaul or replace the engine.
Then go to the next step.
14

INSPECT FUEL LINE PRESSURE

• Perform the "FUEL LINE PRESSURE INSPECTION".
• Is there any malfunction?
Yes
Replace the fuel pump unit, then go to the next step.
No
Go to the next step.
15

VERIFY TROUBLESHOOTING OF DTC P0505 COMPLETED

• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Perform the self-test.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
16

VERIFY AFTER REPAIR PROCEDURE

• Perform the "AFTER REPAIR PROCEDURE".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE.)
No
DTC troubleshooting completed.