For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC C1523 03: System Voltage Low Voltage
DTC C1523 07: System Voltage High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
B+ | C1523 | C1523 | -- | --
Ground | -- | C1523 | -- | --

### Circuit/System Description

The power steering control module (PSCM) monitors the battery voltage through the battery voltage signal circuit. If the PSCM senses that battery voltage is outside of its normal range, DTC C1523 will set. Damage to components, and incorrect data may occur when the voltage is out of range.

### Conditions for Running the DTC

• | The voltage supplied to the control module is in the range of 7-26 volts.

• | The ignition is ON.

• | The engine is running.

### Conditions for Setting the DTC

#### C1523 03

The PSCM detects a system voltage below 9 volts for 5 seconds.

#### C1523 07

The PSCM detects a system voltage above 18 volts for 5 seconds.

### Action Taken When the DTC Sets

• | The PSCM commands the SERVICE POWER STEERING message in the DIC to be displayed ON.

• | The PSCM system is disabled.

### Conditions for Clearing the DTC

The DTC clears when the system voltage returns to a normal range.

### Diagnostic Aids

• | A high or low voltage DTC set in multiple control modules indicates a concern in the charging system.

• | A possible cause of this DTC could be overcharging with a battery charger or jump starting.

• | A high or low voltage value in multiple control modules indicates a concern in the charging system.

### Reference Information

#### Schematic Reference

Power Steering Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Power Steering System Description and Operation

Charging System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Engine running measure and record the voltage at the battery terminals.
2. Verify that the battery voltage is 12.6-15.5 volts

⇒ | If the battery voltage is not within the specified range, refer to Charging System Test

3. Engine running, observe the scan tool EHPS Positive Voltage parameter.
4. Verify that the scan tool displays a value that is within 2 volts of the battery terminal voltage.

### Circuit/System Testing

1. Ignition OFF, Disconnect the harness connectors at the PSCM.
2. Ignition OFF, verify that there is less than 3.0 ohms between the ground circuit terminal 2 X2 and ground.

⇒ | If greater than the specified value, test the ground circuit for an open/high resistance.

3. Ignition ON, verify a test lamp illuminates between the battery positive voltage circuit terminal 1 X2 and ground.

⇒ | If test lamp did not illuminate, test the battery positive voltage circuit for a short to ground or an open/high resistance.

4. Ignition ON, verify a test lamp illuminates between the ignition voltage circuit terminal 1 X1 and ground.

⇒ | If test lamp did not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance.

5. If all circuits test normal, replace the PSCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for PSCM replacement, setup, and programming.