DTC P1289: Manifold Tune Valve Control Circuit: Testing

Turn ignition on. Using scan tool, read DTCs. If GOOD TRIP is displayed and equal to zero, go to next step. If GOOD TRIP is not displayed and equal to zero, go to step 11 .
Turn ignition off. Disconnect MTV solenoid harness connector. MTV solenoid is located on left front of engine, under upper radiator hose. Turn ignition on. Connect a test light between ground and MTV relay output circuit (Brown/Yellow wire) at MTV solenoid harness connector. Using scan tool, actuate MTV relay. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, go to step 10 .
Turn ignition off. Remove MTV relay from Power Distribution Center (PDC). Measure resistance of MTV relay output circuit (Brown/Yellow wire) between MTV solenoid harness connector and MTV relay harness connector terminal No. 56. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Brown/Yellow wire.
Connect a test light between ground and fused battery voltage circuit (Red/Brown wire) at MTV solenoid harness connector terminal No. 55. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open or short in fused battery voltage circuit.
Connect a test light between ground and ASD relay output circuit (Dark Green/Orange wire) at MTV relay harness connector terminal No. 54. Turn ignition on. Using scan tool, actuate ASD relay. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open or short in ASD relay output circuit.
Turn ignition off then on. Connect a test light between battery positive and MTV relay control circuit (Brown/White wire) at MTV relay harness connector terminal No. 58. Using scan tool, actuate MTV relay. If test light does not flash, go to next step. If test light flashes, replace MTV relay.
Turn ignition off. Disconnect PCM harness connectors. PCM is located in engine compartment, between air cleaner and radiator. Measure resistance between ground and MTV relay control circuit (Brown/White wire) at MTV relay harness connector terminal No. 58. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Brown/White wire.
Measure resistance of MTV relay control circuit (Brown/White wire) between MTV relay harness connector terminal No. 58 and terminal No. 39 at PCM C1 harness connector. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Brown/White wire.
If no other possible causes are remaining, replace PCM.
Turn ignition off. Connect a test light between battery positive and ground circuit (Black wire) at MTV solenoid harness connector. If test light illuminates brightly, replace MTV solenoid. If test light does not illuminate brightly, repair open between MTV solenoid and ground point located in left front of engine compartment, on top of core support.
Conditions that set DTC are not present at this time. Perform the following to help identify intermittent condition:
- With engine running at normal operating temperature, wiggle related wiring harness while monitoring related parameters on scan tool. If voltage changes or DTC sets while wiggling wiring harness, repair connectors or wiring harness where wiggling caused voltage to change or DTC to set.
- Review freeze frame information on scan tool. Duplicate conditions present when DTC was set.
- Refer to any Technical Service Bulletins (TSBs) that may apply.
- Visually inspect related wiring harness. Check for chafed, pierced, pinched or partially broken wires.
- Visually inspect related wiring harness connectors. Check for broken, bent, pushed out or corroded terminals.
If a problem is found, repair as necessary. If no problems are found, test is complete.