For 1990-2009 cars

### Circuit Description

The instrument panel module (IPM) is the power mode master and the remote control door lock receiver (RCDLR) is the backup power mode master. The both modules receive the same information from ignition mode switch therefore are able to correctly discern all power modes. There is no degradation in vehicle operation when the backup power mode is active.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1422 Device Power Moding Error

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

DTC Symptom | DTC Symptom Descriptor
--- | ---
52 | Device Power Moding Compare Failure

### Conditions for Running the DTC

Voltage supplied to the module is in the normal operating voltage range of 9-16 volts.

### Conditions for Setting the DTC

The following conditions enable the backup power mode:

• | The RCDLR detects a loss of the power mode message from the IPM.

• | The IPM invalidates the power mode message.

• | The RCDLR senses a change on its ignition mode switch inputs, twice, without receiving the corresponding message from the IPM.

### Action Taken When the DTC Sets

• | The backup power mode becomes the system power mode. This code will set following the setting of the DTC B1440.

• | The Service Vehicle Soon (SVS) indicator will illuminate.

### Conditions for Clearing the DTC

• | A current DTC clears when the malfunction is no longer present.

• | A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

### Diagnostic Aids

The setting of this DTC can be caused by various failures:

• | The ignition mode switch malfunction

• | The ignition mode data input circuits to IPM

• | The IPM malfunction

### Test Description

The number below refers to the step number on the diagnostic table.

1. The setting of any of those DTCs may be followed by the setting of B1422.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Power Distribution Schematics Connector End View Reference: Master Electrical Component List
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Did you retrieve any of the following DTCs?

• | B1380

• | B1385

• | B1440

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 3

3 |

1. Turn OFF the ignition.
2. Disconnect the instrument panel module (IPM).
3. Inspect for poor connections and terminal tension at the harness connector of the IPM. Refer to Testing for Intermittent Conditions and Poor Connections .

Did you find and correct the condition?

--

Go to Step 5

Go to Step 4

4 | Replace the IPM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 5 | --
5 |

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 1

System OK