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B1674






B1674 - Driver Courtesy Lamp Control Circuit High

For a complete wiring diagram, refer to.

Theory of Operation

Whenever the door module is awake, it supplies approximately eight volts on the Door Courtesy Lamp Driver circuit. There is only a 0.2 ma draw on the circuit when the lamp is connected. Therefore, the lamp does not light. If the lamp connector is disconnected, causing an open circuit, this code will set.

When Monitored: Whenever the module is awake.

Set Condition: When the courtesy lamps are off and the Driver Door Courtesy Lamp Driver circuit is shorted to battery voltage or there is no load (open) on the circuit.






Test Step 1 - TEST FOR INTERMITTENT CONDITION

Turn the ignition on.

With the scan tool, record and erase the DTCs.

Turn the courtesy lamps on and then off.

Wait 30 seconds.

With the scan tool, read the DTCs.

Does the scan tool display: B1674-DRIVER COURTESY LAMP CONTROL CIRCUIT HIGH?

Yes

Go to Test Step 2

No

Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 2 - (Z908) GROUND CIRCUIT OPEN







Turn the ignition off.

Remove the inner door panel trim..

Turn the ignition on.

Turn the courtesy lamps off.

Close the doors or trip the door latch to closed.

Using a 12-volt test light connected to 12-volts, check the (Z908) Ground circuit in the Driver Door Courtesy Lamp connector.

Does the test light illuminate brightly?

No

Repair the (Z908) Ground circuit for an open.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Yes

Go to Test Step 3

Test Step 3 - (M43) DRIVER DOOR COURTESY LAMP DRIVER CIRCUIT SHORT TO BATTERY







Using a 12-volt test light connected to ground, check the (M43) Driver Door Courtesy Lamp Driver circuit in the Driver Door Courtesy Lamp connector.

Does the test light illuminate brightly?

No

Go to Test Step 5

Yes

Go to Test Step 4

Test Step 4 - (M43) DRIVER DOOR COURTESY LAMP DRIVER WIRE SHORT TO BATTERY







Turn the ignition off.

Disconnect the Driver Door Module C5 harness connector.

Ensure the courtesy lamps are off.

Turn the ignition on.

Using a 12-volt test light connected to ground, check the (M43) Driver Door Courtesy Lamp Driver circuit.

Does the test light illuminate brightly?

Yes

Repair the (M43) Driver Door Courtesy Lamp Driver circuit for a short to battery. The most probable cause would be a short to the (F921) Fused Ignition Switch Output circuit. Turn the ignition off and recheck. If the test light continues to light, repair the circuit for a short to battery.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Replace the Driver Door Module (DDM).

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 5 - DRIVER DOOR COURTESY LAMP







Turn the courtesy lamps on.

Using a 12-volt test light connected to ground, check the (M43) Driver Door Courtesy Lamp Driver circuit.

Does the test light illuminate brightly?

Yes

Replace the Driver Door Courtesy Lamp.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Go to Test Step 6

Test Step 6 - (M43) DRIVER DOOR COURTESY LAMP DRIVER CIRCUIT OPEN







Turn the ignition off.

Disconnect the Driver Door Module C5 connector.

Measure the resistance of the (M43) Driver Door Courtesy Lamp Driver circuit between the DDM C5 connector and the Lamp connector.

Is the resistance below 5.0 ohms?

Yes

Replace the Driver Door Module.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Repair the (M43) Driver Door Courtesy Lamp Driver circuit for an open.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior