Jeep Wrangler TJ. Manual - part 116

TEST

ACTION

APPLICABILITY

Disconnect the C2 PCM harness connector.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the (K961) IAC Signal circuit from the IAC Motor harness
connector to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

All

Yes

→ Go To 4

→ Repair the open in the (K961) IAC Signal circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

Measure the resistance between ground and the (K961) IAC Signal circuit in the IAC
Motor harness connector.
Is the resistance below 100 ohms?

All

Yes

→ Repair the short to ground in the (K961) IAC Signal circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 5

CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the (K61) IAC Control circuit from the IAC Motor harness
connector to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

All

Yes

→ Go To 6

→ Repair the open in the (K61) IAC Control circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

Measure the resistance between ground and the (K61) IAC Control circuit in the IAC
Motor harness connector.
Is the resistance below 100 ohms?

All

Yes

→ Repair the short to ground in the (K61) IAC Control circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 7

NOTE: Before continuing, check the PCM harness connector terminals for
corrosion, damage, or terminal push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay
particular attention to all Power and Ground circuits.
If there are no possible causes remaining, view repair.

All

Repair

Replace and program the Powertrain Control Module per Service
Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

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DRIVEABILITY - NGC

P0508-IAC VALVE SIGNAL CIRCUIT LOW —

Continued

Symptom:

P0509-IAC VALVE SIGNAL CIRCUIT HIGH

When Monitored and Set Condition:

P0509-IAC VALVE SIGNAL CIRCUIT HIGH

When Monitored:

Engine running. Battery voltage greater than 10 volts. IAC motor

operating.

Set Condition:

The PCM senses a short to ground or battery voltage on the Linear Idle Air

Control (LIAC) control circuit for 2.75 seconds while the IAC motor is active.

POSSIBLE CAUSES

IAC MOTOR OPERATION

IAC MOTOR

(K961) IAC SIGNAL CIRCUIT SHORTED TO VOLTAGE

(K61) IAC CONTROL CIRCUIT SHORTED TO VOLTAGE

(K61) IAC CONTROL CIRCUIT SHORTED TO (K961) IAC SIGNAL CIRCUIT

PCM

TEST

ACTION

APPLICABILITY

NOTE: If the engine will not idle, maintain an engine speed between 800 and
1500 RPM.
Start the engine.
Allow the engine to idle.
Check for vacuum leaks, proper PCV valve installation, proper MAP Sensor instal-
lation, and proper IAC installation.
With the DRBIII

t, read the IAC Current.

Is the IAC Current above 999 mA?

All

Yes

→ Go To 2

→ Refer to the INTERMITTENT CONDITON Symptom (Diagnostic

Procedure).
Perform POWERTRAIN VERIFICATION TEST VER - 5.

Turn the ignition off.
Disconnect the IAC Motor harness connector.
With the DRBIII

t, monitor the IAC Current.

Ignition on, engine not running.
Does the DRBIII

t display IAC Current at 0mA?

All

Yes

→ Replace the IAC Motor.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 3

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DRIVEABILITY - NGC

TEST

ACTION

APPLICABILITY

With the DRBIII

t, actuate the ASD Relay.

Measure the voltage on the (K961) IAC Signal circuit in the IAC Motor harness
connector.
Is the voltage above 0.5 of a volt?

All

Yes

→ Repair the short to voltage in the (K961) IAC Signal circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 4

Measure the voltage on the (K61) IAC Control circuit in the IAC Motor harness
connector.
Is the voltage above 0.5 of a volt?

All

Yes

→ Repair the short to voltage in the (K61) IAC Control circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 5

NOTE: Stop the ASD Relay actuation before continuing.

Turn the ignition off.
Disconnect the C2 PCM harness connector.
Measure the resistance across the (K961) IAC Signal circuit and the (K61) IAC
Control circuit in the IAC Motor harness connector.
Is the resistance below 5.0 ohms?

All

Yes

→ Repair the short between the (K61) IAC Control circuit and the

(K961) IAC Signal circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 6

All

Repair

Replace and program the Powertrain Control Module per Service
Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

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DRIVEABILITY - NGC

P0509-IAC VALVE SIGNAL CIRCUIT HIGH —

Continued

Symptom:

P0513-INVALID SKIM KEY

When Monitored and Set Condition:

P0513-INVALID SKIM KEY

When Monitored:

Ignition on.

Set Condition:

The PCM detects an invalid SKIM key.

POSSIBLE CAUSES

INCORRECT VIN IN PCM

NO COMMUNICATION WITH SKIM

NO VIN PROGRAMMED IN THE PCM

SKIM TROUBLE CODES SET

IGNITION KEY

PCM

TEST

ACTION

APPLICABILITY

Ignition on, engine not running.
With the DRBIII

t, read the PCM DTCs.

Is the Good Trip Counter displayed and equal to zero?

All

Yes

→ Go To 2

→ Go To 7

With the DRBIII

t, attempt to communicate with the SKIM.

Can the DRBIII

t communicate with the SKIM?

All

Yes

→ Go To 3

→ Refer to symptom BUS +/- SIGNAL OPEN FROM SKIM in the

COMMUNICATION category.
Perform SKIS VERIFICATION.

With the DRBIII

t, check for SKIM DTCs.

Are any DTCs present in the SKIM?

All

Yes

→ Refer to BODY information for the related symptom(s).

Perform SKIS VERIFICATION.

→ Go To 4

With the DRBIII

t, display the VIN that is programmed in the PCM.

Has a VIN been programmed into the PCM?

All

Yes

→ Go To 5

→ Program the correct VIN into the PCM and retest.

Perform SKIS VERIFICATION.

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