Diagnostic Aids
NOTE:
After each service or repair procedure has been completed, reconnect all components. Clear DTCs and repeat QUICK TEST procedures to ensure all EEC-V systems are working properly
Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:
- Charge Air Cooler Pump Relay
- Charge Air Cooler Pump Motor
- Wiring Harness Circuit (CAC, VPWR, B+, VPWR & PWR GND). See Fig 1
NOTE:
Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION table of fault code setting condition.
FAULT CODE SETTING CONDITION
| Fault Code | KOEO | KOER | Continuous Memory |
|---|---|---|---|
| P1229 | KP1 | KP1 | KP1 |
- 1) DTC P1229: Check VPWR To CAC Pump Relay Coil
This DTC indicates PCM is requesting CAC pump motor to operate, but voltage is not detected on CAC circuit. Possible causes are:- Internal Open In CAC Pump Motor
- B+ Or VPWR Circuit Open Or Shorted To Ground
- CAC Or CAC PUMP PWR Circuit Open Or Shorted To Ground
- Faulty CAC Pump Relay
- CAC Pump Motor Shorted
- Bad CAC Pump Motor Ground Connection
- Faulty PCM
Turn ignition switch to OFF position. Check fuse No. 23 (15-amp) located in battery junction box in engine compartment. If fuse is okay, go to next step. If fuse is blown, check VPWR circuit (Red/Yellow wire) between fuse No. 23 and CAC pump relay for short to ground. Repair as necessary. Replace blown fuse.
- 2) Check B+ Supply To CAC Pump Relay
Ensure ignition switch is turned to OFF position. Check fuse No. 106 (20-amp) located in battery junction box in engine compartment. If fuse is okay, go to next step. If fuse is blown, check B+ circuit (Orange/Yellow wire) between fuse No. 106 and CAC pump relay, or CAC PUMP PWR circuit (White wire) between CAC pump relay and CAC pump motor for short to ground. Repair as necessary. Replace blown fuse. - 3) Check CAC Pump Motor Ground Circuit
Disconnect CAC pump motor connector. Measure resistance of ground circuit between CAC pump motor harness connector ground terminal and negative battery terminal. If resistance is less than 2 ohms, go to next step. If resistance is 2 ohms or more, check tightness of ground lug. If ground lug is okay, check for open ground circuit. - 4) Check CAC Pump Motor Resistance
Using a DVOM, measure resistance between both CAC pump motor terminals. If resistance is less than 10 ohms, go to next step. If resistance is 10 ohms or more, replace CAC pump motor. - 5) Check CAC Pump Relay
Remove CAC pump motor relay from engine compartment power distribution box. Measure resistance between relay terminal No. 1 and all other relay terminals. Resistance should be 65-90 ohms between terminals No. 1 and 2 and more than 10 k/ohms between terminal No. 1 and all other relay terminals. See Fig 1. If resistance is as specified, go to next step. If resistance is not as specified, replace CAC pump motor relay. - 6) Check CAC Circuit For Open Between PCM & CAC Relay
Disconnect PCM connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Using a DVOM, measure resistance of CAC circuit (White/Orange wire) between PCM harness connector terminal No. 70 and CAC pump motor relay cavity No. 2. See Figure and Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in CAC circuit. - 7) Check CAC Circuit For Short To Ground Between PCM & CAC Pump Motor Relay
Using a DVOM, measure resistance of CAC circuit (White/Orange wire) between negative battery terminal and PCM harness connector terminal No. 70. See Figure. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in CAC circuit. - 8) Check CAC Circuit For Short To VPWR Between PCM & CAC Pump Motor Relay
Ensure CAC relay is removed from battery junction box in engine compartment. Turn ignition switch to ON position. Using a DVOM, measure voltage of CAC circuit between negative battery terminal and PCM harness connector terminal No. 70. If voltage is less than .5 volt, go to next step. If voltage is .5 volt or more, repair short to B+ or VPWR in CAC circuit. - 9) Check VPWR Circuit For Open Between Fuse No. 23 & CAC Pump Motor Relay
Turn ignition switch to OFF position. Ensure fuse No. 23 and CAC pump motor relay are removed from battery junction box in engine compartment. Using a DVOM, measure resistance of VPWR circuit (Red/Yellow wire) between CAC pump motor relay cavity No. 1 and output side of fuse No. 23. See Fig 1. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in VPWR circuit to CAC pump motor relay. - 10) Check B+ Circuit For Open Between Fuse No. 106 & CAC Pump Motor Relay
Ensure ignition switch is turned to OFF position. Ensure fuse No. 106 is removed from battery junction box in engine compartment. Using a DVOM, measure resistance of B+ circuit (Orange/Yellow wire) between CAC pump motor relay cavity No. 3 and output side of fuse No. 106. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in B+ circuit to CAC pump motor relay . - 11) Check CAC PUMP PWR Circuit For Open Between CAC Pump Motor Relay & CAC Pump Motor
Using a DVOM, measure resistance of CAC PUMP PWR circuit (White wire) between CAC pump motor relay cavity No. 5 and CAC pump motor harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in CAC PUMP PWR circuit to CAC pump motor. - 12) Check SCICP PID
Ensure ignition switch is turned to OFF position. Reconnect PCM connector. Install CAC relay and fuses No. 23 and 106. Turn ignition switch to ON position. Using scan tool, select SCICP PID from PID/DATA MONITOR & RECORD menu. If SCICP PID value indicates OFF, no problem is indicated at this time. Go to TEST Z and check for intermittent faults. If SCICP PID value indicates ON, proceed as follows:- Check CAC reservoir level.
- Check for air flow blockage at CAC intercooler.
- Check for high resistance or open circuit in Intake Air Temperature (IAT) 2 sensor and connecting circuits.
- Check for reversed intercooler hoses.
Repair as necessary. If no problems are found and DTC P1229 is present in KOEO and KOER ON-DEMAND SELF-TEST, replace PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Program PCM. See FLASH VEHICLE IDENTIFICATION BLOCK PROCEDURE .