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 B3140 00: Driver Unlock Switch Circuit
DTC B3145 00: Passenger Unlock Switch Circuit
DTC B3150 00: Driver Lock Switch Circuit
DTC B3155 00: Right Front Lock Switch Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
I/P Fuse Block B+ | 1, 2, 3 | 1, 2, 3 | -- | --
Driver Door Lock Switch Lock Signal | B3150 00 | B3150 00 | B3150 00 | --
Driver Door Lock Switch Unlock Signal | B3140 00 | B3140 00 | B3140 00 | --
Passenger Door Lock Switch Lock Signal | B3155 00 | B3155 00 | B3155 00 | --
Passenger Door Lock Switch Unlock Signal | B3145 00 | B3145 00 | B3145 00 | --
Door Latch Control | 1, 2, 3 | 1, 2, 3 | 1, 2, 3 | --
Doors Unlocked Control | B3130 00 | B3130 00 | B3130 00 | --
LF Door Unlock Control | B3125 00 | B3125 00 | B3125 00 | --
Doors Locked Control | B3135 00 | B3135 00 | -- | --
Door Lock Switch Ground | -- | 1, 2, 3 | 1, 2, 3 | --
I/P Fuse Block Ground | -- | 1, 2, 3 | 1, 2, 3 | --
1. Door Lock Malfunction 2. Driver Door Unlock Malfunction 3. Door Unlock Malfunction

### Circuit/System Description

The body control module (BCM) controls the door lock, passenger door unlock and driver door unlock relays. Voltage is applied to the appropriate relay through the door lock/unlock control circuit when the BCM senses a door lock/unlock switch activation or a keyless entry lock or unlock command.

### Conditions for Running the DTC

The system voltage must be between 9-16 volts.

### Conditions for Setting the DTC

#### B3140 00 or B3150 00

The BCM detects a short to ground in the left lock switch or unlock switch signal circuits.

#### B3145 00 or B3155 00

The BCM detects a short to ground in the right lock switch or unlock switch signal circuits.

### Action Taken When the DTC Sets

• | The BCM stores the DTC to memory.

• | The power door locks will not operate.

### Conditions for Clearing the DTC

• | This DTC will change from current to history when the fault is no longer present.

• | A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

### Reference Information

#### Schematic Reference

Door Lock/Indicator Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Power Door Locks 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

Ignition ON, observe the scan tool Driver Door Lock Sw, Psgr Door Lock Sw, Driver Door Unlock Sw and Psgr Door Unlock Sw. parameters while using the appropriate door lock switch. The reading should change between Inactive and Active.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate door lock switch.
2. Ignition ON, verify the scan tool Door Lock Sw. parameter is Inactive.

⇒ | If not the specified value, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the BCM.

3. Verify the scan tool Door Unlock Sw parameter is Inactive.

⇒ | If not the specified value, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, test or replace the door lock switch.

### Component Testing

1. Ignition OFF, disconnect the harness connector at the appropriate door lock switch.
2. Test for infinite resistance between the signal terminals D and E and the ground terminal B with the switch in the open position.

⇒ | If less than the specified value, replace the door lock switch.

3. Test for less than 2 ohms between the signal terminal D and the ground terminal B with the switch in the unlock position.

⇒ | If greater than the specified range, replace the door lock switch.

4. Test for less than 2 ohms between the signal terminal E and the ground terminal B with the switch in the lock position.

⇒ | If greater than the specified range, replace the door lock switch

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Door Lock and Side Window Switch Replacement - Driver Side

• | Door Lock and Side Window Switch Replacement - Passenger Side

• | Control Module References for BCM replacement, setup and programming