Cruze

DTC B3887 or B3888

Ground is applied at all times to the indicator/multifunction switch. When the indicator/multifunction switch is placed in either the turn right or turn left position, ground is applied to the body control module (BCM) through either the right turn or left indicator switch signal circuit. The BCM sends this message to the trailer lighting converter. The trailer lighting converter then applies a voltage to the appropriate trailer indicator lamps through there respective voltage supply circuits.

B3887 02, B3887 04, B3888 02 and B3888 04

The appropriate trailer indicator is active.

B3887 02 or B3888 02

The trailer lighting converter detects a short to ground on the control circuit.

B3887 04 or B3888 04

The trailer lighting converter detects an open control circuit.

The appropriate trailer indicator lamp is inoperative.

The condition for setting the DTC is not longer present.

Schematic Reference

Exterior Lamps Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Exterior Lighting Systems Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, perform the appropriate Trailer Turn Signal Lamp test. The appropriate trailer turn signal lamp should be ON/OFF.

1. Ignition OFF, test for less than 5 Ω between the X88 Trailer Connector terminal 3, 11, 13 and ground.

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

2. Connect a test lamp between the appropriate X88 Trailer Connector terminal listed below and ground.

•	X88 Trailer Connector terminal 1

•	X88 Trailer Connector terminal 4

3. Command the appropriate Trailer Turn Signal Lamp Active/Inactive test with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒	If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K68 Trailer Lighting Control Module.

⇒	If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K68 Trailer Lighting Control Module.

4. If all the circuits test normal, test the appropriate indicator lamp circuit at the trailer.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for trailer lighting converter replacement, setup and programming