P3402

P3402-CYLINDER 1 DEACTIVATION CONTROL PERFORMANCE





For a complete wiring diagram refer to: 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 8 to 4 cylinder mode.

Set Condition
The MDS fails to disengage for cylinder 1.

Possible Causes
- (K451) MDS SOLENOID NO.1 CONTROL SHORT TO VOLTAGE
- OIL PASSAGES RESTRICTED
- LIFTER
- MDS SOLENOID NO.1
- PCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test
1. ACTIVE DTC





Ignition on, engine not running.
With a scan tool, read DTCs.

Is the DTC active at this time?
Yes >> Go To 2
No >> Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
2. MDS SOLENOID NO.1 CONTROL CIRCUIT
Turn the ignition off.
Disconnect the MDS Solenoid No.1 harness connector.
Ignition on, engine not running.
Turn off all accessories.
Using a 12-volt test light connected to ground, probe the (K451) MDS Solenoid No.1 Control circuit.

Does the 12-volt test light illuminate?
Yes >> Go To 3
No >> Go To 4
3. (K451) MDS SOLENOID NO.1 CONTROL CIRCUIT SHORTED TO VOLTAGE





Turn the ignition off. Disconnect the PCM harness connectors.
Turn the ignition on.
Measure the voltage on (K451) MDS Solenoid No.1 Control circuit in the MDS Solenoid No.1 harness connector.

Is voltage present?
Yes >> Repair the short to voltage in the (K451) MDS Solenoid No.1 Control circuit.
Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No >>

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Replace and program the Powertrain Control Module per Service Information.
Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
4. MDS SOLENOID 1





Turn the ignition off.
Remove the Intake Manifold per Service Information.
Turn the ignition on.
With the scan tool actuate the MDS Solenoid 1.

Can you feel and hear the Solenoid Actuating?
Yes >> Go To 5
No >> Remove the Solenoid and check for any debris that may be blocking the oil passages to the Solenoid. If the passages are clogged, clean the pas sages and replace the MDS Solenoid 1. If the passages are not clogged with debris, replace the MDS Solenoid 1.
Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
5. OIL PASSAGES RESTRICTED
Turn the ignition off.
Remove both Solenoids on Bank 1 of the engine block.
Remove the Bank 1 Cylinder Head per Service Information.
Remove the Lifters from the left engine bank.
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 POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No >> Replace both sets of lifters if no other possible causes remain.
Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test