P1417

P1417-CYLINDER 7 REACTIVATION CONTROL PERFORMANCE





For a complete wiring diagram refer to the Wiring Information Electrical Diagrams.

Theory of Operation

When all criteria has been met, power is supplied to each MDS Solenoid when the engine is making a transition from 8 cylinder mode to 4 cylinder mode. By actuating the solenoid, oil pressure is raised to the pair of lifters that coincide with each particular solenoid. The oil pressure pushes in the locking pins that allows the lifter to collapse, decoupling the valves and camshaft.

- When Monitored:
Transition from 4 to 8 cylinder mode.

- Set Condition:
The MDS fails to disengage for cylinder 7. One trip fault.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DTC

NOTE: Diagnose any Misfire DTCs before continuing.

1. Ignition on, engine not running.
2. With a scan tool, select View DTCs.

Is the DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. . Intermittent Condition Test

2. (K454) MDS SOLENOID NO.7 CONTROL CIRCUIT SHORTED TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the C3 PCM harness connector.
3. Disconnect the C112 In-line harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install PCM Pinout Box 8815 to perform diagnosis.

4. Turn the ignition on.
5. Measure the voltage on (K454) MDS Solenoid No.7 Control circuit in the appropriate terminal of special tool #8815.

Is there any voltage present?

Yes

- Repair the short to voltage in the (K454) MDS Solenoid No.7 Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 3

3. MDS SOLENOID RESISTANCE




1. Turn the ignition off.
2. Reconnect the C112 In-line harness connector.
3. Measure the resistance between the (Z42) Ground Circuit and the (K454) MDS Solenoid No.7 Control Circuit in the appropriate terminals of special tool #8815.

NOTE: It is important to follow the below temp/resistance values to ensure an accurate reading.






Is the resistance within an acceptable range?

Yes

- Go To 4

No

- Visually and Physically inspect the wiring harness between the C112 connector and the MDS Solenoid connector. Repair as necessary. If OK, replace the MDS Solenoid.

4. PCM CONTROL




1. Turn the ignition off.
2. Reconnect the PCM harness connector.
3. Disconnect the C112 In-line harness connector.
4. Ignition on, engine not running.
5. Using a 12-volt test light connected to the (Z42) Ground circuit, probe the (K454) MDS Solenoid No.7 Control circuit in the C112 In-line harness connector.
6. With a scan tool, actuate the MDS Solenoid.

NOTE: The test light should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows 100% actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 25% actuation, the brightness should be 25% as bright as a direct connection to the battery.

Does the 12-volt test light flash on and off?

Yes

- Go To 5

No

- Replace and program the Powertrain Control Module.Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. MDS SOLENOID 7




1. Turn the ignition off.
2. Remove the Intake Manifold.
3. Turn the ignition on.
4. With the scan tool actuate the MDS Solenoid 7.

Can you feel and hear the Solenoid Actuating?

Yes

- Go To 6

No

- Remove the Solenoid (1) and check for any debris that may be blocking the oil passages (3) to the Solenoid. If the passages are clogged, clean the passages and replace the MDS Solenoid 7. If the passages are not clogged with debris, replace the MDS Solenoid 7.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

6. OIL PASSAGES RESTRICTED
1. Turn the ignition off.
2. Remove both Solenoids on Bank 1 of the engine block.
3. Remove the Bank 7 Cylinder Head.
4. Remove the Lifters from the right engine bank.
5. Inspect the oil passages to the Solenoids and from the Solenoids to the lifters.

Are the passages blocked?

Yes

- Clean the oil passages as necessary. If the entire engine is restricted disassembly of the entire engine block may be necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace both sets of lifters if no other possible causes remain.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.