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Pinpoint Test

CHECK THE ATC SOLENOID AND CONTROL CIRCUITS FOR AN OPEN WITH THE ATC SOLENOID CONNECTED

Ignition OFF.
Disconnect: AWD Relay Module.
Measure:

AWD Relay Module			AWD Relay Module

C4379			C4379
Pin	Circuit	Measurement / Action	Pin	Circuit
5	CCF21 (VT/WH)		8	RCF21 (WH/VT)

Is the resistance less than 10 ohms?

Yes: GO to 3.
No : GO to 2 .

CHECK THE ATC SOLENOID CONTROL CIRCUITS FOR AN OPEN

Disconnect: ATC Solenoid.
Measure:

AWD Relay Module			ATC Solenoid

C4379			C4347
Pin	Circuit	Measurement / Action	Pin	Circuit
5	CCF21 (VT/WH)		1	CCF21 (VT/WH)
8	RCF21 (WH/VT)		2	RCF21 (WH/VT)

Are the resistances less than 3 ohms?

Yes: INSTALL a new rear axle assembly. REFER to AXLE ASSEMBLY .
No : REPAIR the affected circuit(s) for an open.

CHECK THE ATC SOLENOID CONTROL CIRCUITS FOR A SHORT TO VOLTAGE

Disconnect: ATC Solenoid.
Ignition ON.
Measure:

AWD Relay Module			Ground

C4379			Ground
Pin	Circuit	Measurement / Action	Pin	Circuit
5	CCF21 (VT/WH)		-	Ground
8	RCF21 (WH/VT)		-	Ground

Is any voltage present?

Yes: REPAIR the affected circuit(s) for a short to voltage.
No : GO to 4 .

CHECK THE ATC SOLENOID CONTROL CIRCUITS FOR A SHORT TO GROUND

Ignition OFF.
Measure:

AWD Relay Module			Ground

C4379			Ground
Pin	Circuit	Measurement / Action	Pin	Circuit
5	CCF21 (VT/WH)		-	Ground
8	RCF21 (WH/VT)		-	Ground

Are the resistances greater than 10, 000 ohms?

Yes: GO to 5 .
No : REPAIR the affected circuit(s) for a short to ground.

CHECK THE ATC SOLENOID CONTROL CIRCUITS FOR A SHORT TOGETHER

Measure:

AWD Relay Module			AWD Relay Module

C4379			C4379
Pin	Circuit	Measurement / Action	Pin	Circuit
5	CCF21 (VT/WH)		8	RCF21 (WH/VT)

Is the resistance greater than 10, 000 ohms?

Yes: GO to 6 .
No : REPAIR the affected circuit(s) for a short together.

CHECK FOR CORRECT AWD RELAY MODULE OPERATION
1. Ignition OFF.
2. Disconnect and inspect all PCM connectors and the AWD relay module connector.
3. Repair:
  - corrosion (install new connector or terminals - clean module pins)
  - damaged or bent pins - install new terminals/pins
  - pushed-out pins - install new pins as necessary
4. Reconnect the PCM connectors and the AWD relay module connector. Make sure they seat and latch correctly.
5. Operate the system and determine if the concern is still present.
Is the concern still present?
1. Yes: CHECK OASIS for any applicable TSBs . If a TSB exists for this concern, discontinue this test and follow TSB instructions. If no TSBs address this concern, INSTALL a new AWD relay module. REFER to All-Wheel Drive (AWD) Relay Module . CLEAR all DTCs . REPEAT self-test. If DTC P188B is retrieved again, INSTALL a new PCM. REFER to POWERTRAIN CONTROL MODULE (PCM) - 3.5L TI-VCT
2. No : The system is operating correctly at this time. The concern may have been caused by module connections. Address the root cause of any connector or pin issues.