DTC P0505 [L8, LF]

id0102b1808500

DTC P0505 | Idle speed control system problem
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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
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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. (See ON-BOARD DIAGNOSTIC TEST [L8, LF].) • 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. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L8, LF].) • 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. (See COMPRESSION INSPECTION [L8, LF].) • 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. (See AFTER REPAIR PROCEDURE [L8, LF].) • Perform the KOER self test. (See KOEO/KOER SELF TEST [L8, LF].) • 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”. (See AFTER REPAIR PROCEDURE [L8, LF].) • Are any DTCs present? | Yes | Go to the applicable DTC troubleshooting. (See DTC TABLE [L8, LF].)
No | DTC troubleshooting completed.