DTC P0505

Idle speed control system problem

DETECTION CONDITION

• The PCM cannot control idle speed toward target idle speed while KOER self test.

POSSIBLE CAUSE

• Drive-by-wire control system malfunction

• Air cleaner element clogged

• Air intake passage clogged

• A/C relay control circuit malfunction

• Generator control circuit malfunction

• Low engine compression (Over capacity of blow-by gas)

• PCM malfunction

STEP

INSPECTION

ACTION

1

• Verify related Service Bulletins and/or on-line 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.

2

• Turn the ignition switch off then to the ON position. (Engine off)

• Verify pending code or stored DTCs using the M-MDS.

• Does DTC P0506, P0507, P0638, P2101, P2107, P2108, P2109, P2112 or P2119 presents?

Yes

Perform the applicable DTC troubleshooting.

(See DTC TABLE [LF].)

No

Go to the next step.

3

• Perform Electronic Throttle control system inspection.

  (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [LF].)

• Does Electronic Throttle control system work properly?

Yes

Go to the next step.

No

Repair or replace malfunctioning part, according to inspection results.

Then go to Step 9.

4

NOTE:

• The following test should be performed for the A/C. Go to the next step for vehicles without A/C

• Turn the fan switch off.

• Is the magnetic clutch still on?

Yes

Go to “A/C ALWAYS ON / A/C COMPRESSOR RUNS CONTINUOUSLY.” of ENGINE SYMPTOM TROUBLESHOOTING then go to Step 9.

(See SYMPTOM DIAGNOSTIC INDEX [LF].)

No

Go to the next step.

5

• Apply electrical load.

• Is the engine speed increased?

Yes

Go to the next step.

No

Repair short to power supply in generator control circuit, then go to Step 9.

6

• Remove air cleaner element with the engine running.

• Is the engine speed increased?

Yes

Clean or replace the air cleaner element, then go to Step 9.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF].)

No

Go to the next step.

7

• Is the throttle body clogged?

Yes

Clean or replace the throttle body passage, then go to Step 9.

No

Go to the next step.

8

• Inspect engine compression.

  (See COMPRESSION INSPECTION [LF].)

• Is engine compression normal?

Yes

Go to the next step.

No

Overhaul the engine, then go to the next step.

9

• Make sure to reconnect all disconnected connectors.

• Clear the DTC using the M-MDS.

• Perform the KOER self-test.

  (See KOEO/KOER SELF TEST [LF].)

• Is the same DTC present?

Yes

Replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [LF].)

No

Go to the next step.

10

• Perform the “AFTER REPAIR PROCEDURE”.

  (See AFTER REPAIR PROCEDURE [LF].)

• Are any DTC present?

Yes

Go to the applicable DTC troubleshooting.

(See DTC TABLE [LF].)

No

Troubleshooting completed.