GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The power steering control module (PSCM) has a discrete battery positive voltage supply circuit. The PSCM monitors the voltage level on this circuit to ensure the electric power steering (EPS) system has adequate voltage levels to perform the system functions.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0895 Device Voltage

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description .

DTC Symptom

DTC Symptom Descriptor

03

Voltage Below Threshold

11

Above Maximum Threshold

12

Below Minimum Threshold

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

EPS system battery voltage is less than 9.55 volts or greater than 17.5 volts.

Action Taken When the DTC Sets

    • The instrument panel cluster (IPC) message center displays the PWR STR warning message.
    • Steering assist is reduced.

Conditions for Clearing the DTC

    • A current DTC will clear when EPS system voltage is 9.55-17.5 volts.
    • A history DTC will clear after 100 consecutive ignition cycles with EPS system voltage between 9.55-17.5 volts.

Diagnostic Aids

The scan tool can be used to view the number of times a low battery voltage incident has occurred. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections for further diagnosis.

Test Description

The numbers below refer to the step number on the diagnostic table.

  1. This step tests if the malfunction exists in the vehicles charging system.

  2. This step tests if the malfunction is intermittent.

Step

Action

Yes

No

Schematic Reference: Power Steering Schematics

Connector End Views Reference: Power Steering Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Battery Voltage parameter in the engine control module (ECM)/powertrain control module (PCM) Data List.

Does the scan tool display 9.55-17.5 volts?

Go to Step 3

Go to Charging System Test

3

With a scan tool, observe the Battery Voltage parameter in the electric power steering (EPS) Data List 1.

Does the scan tool display 9.55-17.5 volts?

Go to Diagnostic Aids

Go to Step 4

4

Test the battery positive voltage circuit of the power steering control module (PSCM) for a high resistance. Refer to Circuit Testing and to Wiring Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 5

5

Test the ground circuit of the PSCM for a high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Inspect for poor connections at the harness connector of the underhood fuse block stud terminal. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 7

7

Inspect for poor connections at the harness connector of the PSCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 8

8

Inspect for poor connections at the ground terminal G109 . Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 9

9

Replace the EPS assembly. Refer to Steering Column Replacement .

Did you complete the replacement?

Go to Step 10

--

10

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does DTC C0895 reset?

Go to Step 2

System OK