DTC P0505 [L8, LF]

id0102b1808500

DTC P0505

Idle speed control system problem
DETECTION CONDITION
•  The PCM cannot control idle speed toward target idle speed while the KOER self test.
Diagnostic support note
•  The MIL does not illuminate.
•  FREEZE FRAME DATA (Mode 2/Mode 12) is not available.
•  The DTC is not stored in the PCM memory.
POSSIBLE CAUSE
•  Drive-by-wire control system malfunction
•  A/C relay control circuit malfunction
•  Generator control circuit malfunction
•  Air cleaner element clogged
•  Air intake passage clogged
•  Low engine compression (Over capacity of blow-by gas)
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY RELATED SERVICE 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.
2
VERIFY RELATED PENDING CODE AND STORED DTC
•  Turn the ignition switch off then to the ON position. (engine off)
•  Perform the Pending Trouble Code Access Procedure and DTC Reading Procedure.
•  Is the DTC P0506, P0507, P0638, P2101, P2107, P2108, P2109, P2112 or P2119 also present?
Yes
Go to the applicable DTC troubleshooting.
(See DTC TABLE [L8, LF].)
No
Go to the next step.
3
INSPECT ELECTRONIC THROTTLE CONTROL SYSTEM OPERATION
•  Perform the Electronic Throttle Control System Inspection.
•  Does the electronic throttle control system work properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results, then go to Step 9.
4
INSPECT A/C MAGNETIC CLUTCH OPERATION
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
Perform the symptom troubleshooting “NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY”.
(See NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [L8, LF].)
No
Go to the next step.
5
INSPECT GENERATOR CONTROL CIRCUIT MALFUNCTION
•  Apply the electrical load.
•  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 in generator control circuit, then go to Step 9.
6
INSPECT AIR CLEANER ELEMENT
•  Remove the 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 [L8, LF].)
No
Go to the next step.
7
INSPECT THROTTLE BODY PASSAGE
•  Visually inspect the throttle body passage.
•  Is the throttle body passage clogged?
Yes
Clean or replace the throttle body passage, then go to Step 9.
No
Go to the next step.
8
INSPECT ENGINE COMPRESSION
•  Inspect the engine compression.
•  Is there any malfunction?
Yes
Perform the engine overhaul for repairs, then go to the next step.
No
Go to the next step.
9
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Perform the KOER self test.
•  Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [L8, LF].)
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC troubleshooting.
(See DTC TABLE [L8, LF].)
No
DTC troubleshooting completed.