KP: Charge Air Cooler Pump (CAC)

KP: Introduction See: KP: Charge Air Cooler Pump (CAC) - Introduction

KP1 P1229: CHECK POWER FEED TO CAC PUMP RELAY COIL

• Check Fuse 23.

Is the fuse OK?
Yes

• GO to KP2

.

No

• CHECK Circuit 391 and 369 for short to ground.

KP2 CHECK POWER FEED TO CAC PUMP RELAY

• Check Fuse 106.

Is the fuse OK?
Yes

• GO to KP3

.

No

• CHECK Circuit 17 and 18 for short to ground.

KP3 CHECK INTEGRITY OF CAC PUMP GROUND CONNECTION

• Disconnect the CAC pump.
• Measure the resistance between chassis ground circuit at the CAC pump connector and battery negative post.

Is the resistance less than 2 ohms?
Yes

• GO to KP4

.

No

• CHECK the tightness of the ground lug. If tight check wire back

to the CAC connector.

KP4 CHECK CAC PUMP MOTOR RESISTANCE

• Disconnect the CAC pump motor.
• Measure the resistance between the pins at the CAC connector to the pump motor.

Is the resistance less than 10 ohms?
Yes

• GO to KP5

.

No

• REPLACE CAC pump motor.

KP5 CHECK CAC PUMP RELAY

• Remove relay from power distribution box.
• Measure resistance between pin 1 or 2 and all other pins. One reading must be between 65-90 ohms and all other readings must be greater than 10K ohms.

Are resistance checks OK?
Yes

• GO to KP6

.

No

• REPLACE CAC pump relay.

KP6 CHECK FOR OPEN CAC CIRCUIT BETWEEN PCM AND CAC RELAY

Note: Refer to PCM Pin numbers in the beginning of this pinpoint test.

• Key off.
• Disconnect the PCM and the CAC pump relay.
• Measure the resistance of the CAC circuit at the PCM harness connector and pin 2 of the relay socket.

Is the resistance less than 5 ohms?
Yes

• GO to KP7

.

No

• REPAIR open circuit.

KP7 CHECK CAC CIRCUIT BETWEEN PCM AND CAC RELAY FOR SHORT TO GROUND

• Key off.
• Measure the resistance of the CAC circuit at the PCM harness connector and the battery negative post.

Is the resistance greater than 10K ohms?
Yes

• GO to KP8

.

No

• REPAIR short to ground condition.

KP8 CHECK CAC CIRCUIT BETWEEN PCM AND CAC RELAY FOR SHORT TO POWER

• Key on, engine off.
• Remove CAC pump relay.
• Measure the voltage between the CAC circuit at the PCM harness connector and the battery negative post.

Is the voltage less than 0.05 volt?
Yes

• GO to KP9

.

No

• REPAIR short to B+.

KP9 CHECK FOR OPEN CIRCUIT BETWEEN CAC PUMP RELAY COIL AND POWER FEED

• Remove the CAC pump relay and fuse 23.
• Measure the resistance between relay socket pin 1 and fuse 23 (load side).

Is resistance less than 5 ohms?
Yes

• GO to KP10

.

No

• REPAIR open circuit.

KP10 CHECK FOR OPEN POWER FEED CIRCUIT AT CAC PUMP MOTOR RELAY

• Remove CAC Pump Relay and fuse 106 from their sockets.
• Measure resistance between relay socket pin 3 and load side of fuse socket.

Is resistance less than 5 ohms?
Yes

• GO to KP11

.

No

• REPAIR open circuit.

KP11 CHECK FOR OPEN CAC CIRCUIT BETWEEN CAC, CAC PUMP RELAY AND PUMP MOTOR

• Disconnect the CAC pump motor.
• Measure resistance between relay socket pin 5 and the CAC harness connector.

Is the resistance less than 5 ohms?
Yes

• Replace CAC RELAY, FUSE 23, AND FUSE 106.GO to KP12.

No

• REPAIR open circuit.

KP12 CHECK STATUS OF PID

• Key on, engine off.
• Access SCIPC PID.

Does the SCIPC indicate PID on?
Yes

• If the CAC reservoir is full, no air flow blockage at the CAC

radiator, the IAT 2 and connecting circuits are not high resistance or open
circuited, intercooler hoses are not reversed and DTC P1229 is present in
KOEO and KOER, then REPLACE PCM.

No

• Unable to duplicate or identify fault at this time. GO to Z1 See: Diagnostic Trouble Code Tests and Associated Procedures\SECTION 5: Pinpoint Tests\Z: Intermittent - Pinpoint Test

.