Low Engine Oil Level Indicator Always On

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Step	Action	Yes	No
Schematic Reference: Instrument Cluster Schematics Connector End View Reference: Master Electrical Component List
1	Did you perform the Instrument Cluster Diagnostic System Check?	Go to Step 2	Go to Diagnostic System Check - Instrument Cluster
2	Install a scan tool. Turn the ignition ON, with the engine OFF. With the scan tool, observe the Engine Oil Level Switch parameter in the PCM Engine Data 2 data list. Does the Engine Oil Level Switch parameter display OK?	Go to Step 3	Go to Step 4
3	Does the CHECK ENG OIL LEVEL indicator remain illuminated after the displays test?	Go to Step 11	Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
4	Turn the ignition OFF. Disconnect the engine oil level switch. Connect a 3-ampere fused jumper between the signal circuit of the engine oil level switch and a good ground. Turn the ignition ON, with the engine OFF. With the scan tool, observe the Engine Oil Level Switch parameter. Does the Engine Oil Level Switch parameter display OK?	Go to Step 6	Go to Step 5
5	Test the signal circuit of the engine oil level switch for a short to battery voltage, for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 12	Go to Step 8
6	Test the ground circuit of the engine oil level switch for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 12	Go to Step 7
7	Inspect for poor connections at the harness connector of the engine oil level switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 12	Go to Step 9
8	Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 12	Go to Step 10
9	Replace the engine oil level switch. Refer to the following procedures: Engine Oil Level Sensor and/or Switch Replacement in Engine Mechanical - 4.3L Engine Oil Level Sensor and/or Switch Replacement in Engine Mechanical - 4.8L, 5.3L and 6.0L Engine Oil Level Sensor and/or Switch Replacement in Engine Mechanical - 6.6L (LB7) Engine Oil Level Sensor and/or Switch Replacement in Engine Mechanical - 6.6L (LLY) Engine Oil Level Sensor and/or Switch Replacement in Engine Mechanical - 8.1L Did you complete the replacement?	Go to Step 12	-
10	IMPORTANT: Program the replacement PCM. Replace the PCM. Refer to the following procedures: Powertrain Control Module (PCM) Replacement in Engine Controls - 4.3L Powertrain Control Module (PCM) Replacement in Engine Controls - 4.8L, 5.3L and 6.0L Engine Control Module (ECM) Replacement in Engine Controls - 6.6L (LB7) Engine Control Module (ECM) Replacement in Engine Controls - 6.6L (LLY) Powertrain Control Module (PCM) Replacement in Engine Controls - 8.1L Did you complete the replacement?	Go to Step 12	-
11	IMPORTANT: Program the replacement IPC. Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement .Did you complete the replacement?	Go to Step 12	-
12	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2