DTC P0579:00 [L8, LF, L5]

id010242087000

DTC P0579:00

Cruise control multi-function input circuit range/performance

DETECTION CONDITION

•  The PCM monitors the input signal from the cruise control switch. If the input signal does not change for 120 s, the PCM determines that the cruise control switch circuit has a malfunction.

Diagnostic support note

•  This is a continuous monitor (Other).

•  The MIL does not illuminate.

•  FREEZE FRAME DATA is not available.

•  The DTC is stored in the PCM memory.

POSSIBLE CAUSE

•  Cruise control switch malfunction

•  Open circuit in wiring harness between cruise control switch terminal B and PCM terminal 1AQ

•  Open circuit in wiring harness between cruise control switch terminal D and PCM terminal 1AN

•  Short to power supply in wiring harness between cruise control switch terminal B and PCM terminal 1AQ

•  Short to power supply in wiring harness between cruise control switch terminal D and PCM terminal 1AN

•  Short to ground in wiring harness between cruise control switch terminal B and PCM terminal 1AQ

•  Short to ground in wiring harness between cruise control switch terminal D and PCM terminal 1AN

•  PCM malfunction

DTC P0579:00	Cruise control multi-function input circuit range/performance
DETECTION CONDITION	• The PCM monitors the input signal from the cruise control switch. If the input signal does not change for 120 s, the PCM determines that the cruise control switch circuit has a malfunction. Diagnostic support note • This is a continuous monitor (Other). • The MIL does not illuminate. • FREEZE FRAME DATA is not available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• Cruise control switch malfunction • Open circuit in wiring harness between cruise control switch terminal B and PCM terminal 1AQ • Open circuit in wiring harness between cruise control switch terminal D and PCM terminal 1AN • Short to power supply in wiring harness between cruise control switch terminal B and PCM terminal 1AQ • Short to power supply in wiring harness between cruise control switch terminal D and PCM terminal 1AN • Short to ground in wiring harness between cruise control switch terminal B and PCM terminal 1AQ • Short to ground in wiring harness between cruise control switch terminal D and PCM terminal 1AN • 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.
1		No	Record FREEZE FRAME DATA on the repair order, then go to the next step.
2	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.
2		No	Go to the next step.
3	INSPECT POOR CONNECTION OF CRUISE CONTROL SWITCH CONNECTOR • Switch the ignition to off. • Disconnect the cruise control switch connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the terminal and/or connector, then go to Step 9.
3		No	Go to the next step.
4	IINSPECT CRUISE CONTROL SWITCH CIRCUIT FOR SHORT TO POWER SUPPLY • Switch the ignition to ON (Engine off). • Measure the voltage between the following terminals: ― Cruise control switch terminal B and body ground ― Cruise control switch terminal D and body ground • Are there voltage B+?	Yes	Repair or replace suspected part, then go to Step 9.
4		No	Go to the next step.
5	INSPECT CRUISE CONTROL SWITCH CIRCUIT FOR SHORT TO GROUND • Switch the ignition to off. • Inspect for continuity between the following terminals: ― Cruise control switch terminal B and body ground ― Cruise control switch terminal D and body ground • Are there continuity?	Yes	Repair or replace suspected part, then go to Step 9.
5		No	Go to the next step.
6	INSPECT POOR CONNECTION OF PCM CONNECTOR • Switch the ignition to off. • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the terminal and/or connector, then go to Step 9.
6		No	Go to the next Step.
7	INSPECT CRUISE CONTROL SWITCH CIRCUIT FOR OPEN • Disconnect the PCM connector. • Inspect for continuity between the following terminals: ― Cruise control switch terminal B and PCM terminal 1AQ ― Cruise control switch terminal D and PCM terminal 1AN • Are there continuity?	Yes	Go to the next step.
7		No	Repair or replace suspected part, then go to Step 9.
8	INSPECT CRUISE CONTROL SWITCH • Inspect the cruise control switch. (See CRUISE CONTROL SWITCH INSPECTION [L8, LF, L5].) • Is there malfunction?	Yes	Replace the cruise control switch, then go to the next step. (See STEERING SWITCH REMOVAL/INSTALLATION.)
8		No	Go to the next step.
9	VERIFY TROUBLESHOOTING OF DTC P0579:00 HAS BEEN COMPLETED • Verify that all disconnected connectors are reconnected. • Switch the ignition to ON (Engine off). • Clear the DTC from the PCM memory using the M-MDS. • Perform the “KOEO and KOER self-test”. (See KOEO/KOER SELF TEST [L8, LF, L5].) • Retrieve DTCs using the M-MDS. • Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [L8, LF, L5].)
9		No	Go to the next step.
10	VERIFY AFTER REPAIR PROCEDURE • Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE [L8, LF, L5].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L8, LF, L5].)
10		No	Troubleshooting completed.