GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2009 🢒 Vibe - AWD 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC C1551

Circuit Description

The power steering control module distinguishes the ignition switch status as On or Off through the IG power source circuit.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C1551 IG Power Supply Voltage Malfunction

Conditions for Running the DTC

This DTC shall run when key is inserted into key cylinder.

Conditions for Setting the DTC

The IG power source circuit malfunction inside the power steering control module.

Action Taken When the DTC Sets
    • Power assist stops.
    • The P/S warning indicator illuminates.

Conditions for Clearing the DTC

The DTC will clear when conditions for setting the DTC have been repaired.

Diagnostic Aids

If the steering column or power steering control module has been replaced, the rotation angle sensor initialization and torque sensor zero point calibration, must be performed. Refer to Steering Angle Sensor Initialization and Steering Shaft Torque Sensor Zero Point Calibration .

Step

Action

Value(s)

Yes

No

Schematic Reference: Power Steering Schematics

Connector End View Reference: Component Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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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 the scan tool, observe the Ignition Voltage parameter in the data list.

Does the ignition voltage measure within the specified value?

11 - 14 Volts

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3
  1. Turn the ignition OFF.
  2. Using a DMM, check ECU-IG Fuse resistance.

Is resistance value as specified?

Below 1 Ohm

Go to Step 4

Go to Step 6

4
  1. Disconnect the E32 and A75 connectors from the power steering control module.
  2. Turn the ignition On, with the engine Off.
  3. Measure the voltage between connector E32 terminal 6 and body ground.
  4. Turn the ignition Off.
  5. Measure the resistance between connector A75 terminal 2 and body ground.

Is the voltage and resistance measured within the specified value?

Voltage: 11 -14 Volts

Resistance: Below 1 Ohm

Go to Step 6

Go to Step 5

5

Repair or replace the ignition voltage and/or ground circuit. Refer to Wiring Repairs or Connector Repairs .

Did you complete the repair or replacement?

 

Go to Step 8

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6

Replace ECU-IG Fuse.

Did you complete the replacement?

--

Go to Step 8

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7

Replace the power steering control module. Refer to Control Module References for power steering control module replacement, setup and programming.

Did you complete the replacement?

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Go to Step 8

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8
  1. Use the scan tool in order to clear the DTC.
  2. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK