GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2005 🢒 XLR 🢒 Engine 🢒 Engine Controls - 4.6L (LH2) 🢒 DTC P2088, P2090, P2092, or P2094

Circuit Description

The camshaft position (CMP) actuator system is comprised of 4 CMP actuator solenoids, 4 oil control valves, and 4 CMP actuators. The engine control module (ECM) sends an electrical signal through the control circuits to the CMP actuator solenoids when a cam timing change is desired. The ground circuits of the CMP actuator solenoids are used as a return. If the ECM detects low voltage condition on one of these circuits, DTC P2088, P2090, P2092, P2094 sets.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC P2088 Intake Camshaft Position (CMP) Actuator Solenoid Control Circuit Low Voltage Bank 1
    • DTC P2090 Exhaust Camshaft Position (CMP) Actuator Solenoid Control Circuit Low Voltage Bank 1
    • DTC P2092 Intake Camshaft Position (CMP) Actuator Solenoid Control Circuit Low Voltage Bank 2
    • DTC P2094 Exhaust Camshaft Position (CMP) Actuator Solenoid Control Circuit Low Voltage Bank 2

Conditions for Running the DTC
    • DTCs P0010, P0013, P0020, P0023, P2088, P2089, P2090, P2091, P2092, P2093, P2094, P2095 are not set.
    • The engine is running.
    • The CMP actuator has been commanded for more than 1 second.
    • The ignition voltage is between 11-26 volts.
    • DTC P2088, P2090, P2092, or P2094 runs continuously once the above conditions are met.

Conditions for Setting the DTC

The ECM detects a low voltage condition on a CMP actuator solenoid control circuit for more than 1.6 seconds.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

The CMP actuator system will be disabled until the end of the ignition cycle.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

Go to Step 3

Go to Intermittent Conditions

3

Important: 

   • The scan tool will command the intake camshaft position (CMP) actuators as a set, and the exhaust CMP actuators as a set.
   • The CMP actuator output function will automatically raise the engine speed.

  1. Turn OFF the ignition.
  2. Disconnect the affected CMP actuator solenoid.
  3. Connect a test lamp between the control circuit of the affected CMP actuator solenoid and a good ground.
  4. Start the engine.
  5. Observe the test lamp while you command the affected CMP actuator to 30 degrees with a scan tool.
  6. Turn OFF the ignition.

Did the test lamp illuminate when commanded with a scan tool?

Go to Step 5

Go to Step 4

4

Test the control circuit of the affected CMP actuator solenoid for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 6

5

Test for shorted terminals at the affected CMP actuator solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Test for shorted terminals at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the affected CMP actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake , Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Exhaust , Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake or Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Exhaust .

Did you complete the replacement?

Go to Step 9

--

8

Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 9

--

9
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle with in the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

Go to Step 3

Go to Step 10

10

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

System OK