Diagnostic Aids
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The VLOM solenoids are assigned to the following engine cylinders:
- Solenoid #1 = Cylinder #1
- Solenoid #2 = Cylinder #4
- Solenoid #3 = Cylinder #6
- Solenoid #4 = Cylinder #7
IMPORTANT:
This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test
.
- Remove and inspect the fuse for the valve lifter oil manifold assembly.
- If the fuse is open, then a short to ground condition exists in the circuit.
- Ignition ON, engine OFF, measure and record the ignition voltage at the fuse for the valve lifter oil manifold (VOLM) assembly.
- Connect a DMM in series with a 15A fused jumper wire and a non-fused jumper wire across the exposed fuse terminals in the underhood fuse block.
- Select the 10A range and zero out the DMM display.
- Command each VLOM solenoid ON with a scan tool.
- Record the amperage reading display on the DMM for each solenoid.
- If zero current is detected, then an open circuit condition exists in the circuit.
- Calculate the resistance for each solenoid circuit. The total resistance for each solenoid circuit should be within 11-22 ohms.
- If the total circuit resistance exceeds 22 ohms, an open/high resistance condition exists in the circuit.