P3402
P3402 CYLINDER 1 DEACTIVATION CONTROL PERFORMANCEP3402 - Cylinder 1 Deactivation Control Performance:
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. One trip fault.
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. Initial Inspection and Diagnostic Overview
Diagnostic Test
1. ACTIVE DTC
Ignition on, engine not running.
With a scan tool, read DTCs.
Q: Is the DTC active at this time?
YES: Go To 2
NO: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Component Tests and General Diagnostics
Perform the 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.
Q: 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 C3 PCM harness connector.
Turn the ignition on.
Measure the voltage on (K451) MDS Solenoid No.1 Control circuit in the MDS Solenoid No.1 harness connector.
Q: Is voltage present?
YES: Repair the short to voltage in the (K451) MDS Solenoid No.1 Control circuit. Perform the 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. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
4. MDS SOLENOID 1
Turn the ignition off.
Remove the Intake Manifold.
Turn the ignition on.
With the scan tool actuate the MDS Solenoid 1.
Q: 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 passages and replace the MDS Solenoid 1. If the passages are not clogged with debris, replace the MDS Solenoid 1. Perform the 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.
Remove the Lifters from the left engine bank.
Inspect the oil passages to the Solenoids and from the Solenoids to the lifters.
Q: 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