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.

### Circuit/System Description

Ignition 1 voltage is supplied directly to the water in fuel lamp. The engine control module (ECM) turns the water in fuel lamp ON by sending a request to the instrument panel cluster (IPC) via the CAN communication circuit. The ECM monitors the amount of water in the fuel with a sensor located in the fuel filter assembly. When the water in the fuel is above an acceptable level, the ECM sends a request to illuminate the water in fuel lamp.

### Reference Information

#### Schematic Reference

Instrument Cluster Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Instrument Cluster 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. Ignition ON, observe the DTC information with a scan tool. Verify that DTC U0100, U0155, or U2105 is not set.

⇒ | If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.

2. Command the water in fuel lamp ON and OFF with a scan tool. The water in fuel lamp should respond to the scan tool commands.

⇒ | If the water in fuel lamp does not respond properly, replace the IPC.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• | Water-in-Fuel Draining

• | Control Module References for Instrument Panel Cluster replacement, setup, and programming