DTC B3885 or B3886
Diagnostic Instructions
DTC Descriptors
| DTC B3885 02: Trailer Left Tail Lamp Circuit
Short to Ground |
| DTC B3885 04: Trailer Left Tail Lamp Circuit
Open |
| DTC B3886 02: Trailer Right Tail Lamp Circuit
Short to Ground |
| DTC B3886 04: Trailer Right Tail Lamp Circuit
Open |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Trailer Left Tail Lamp Control
|
3885 02
|
3885 04
|
-
|
-
|
Trailer Right Tail Lamp Control
|
B3886 02
|
B3886 04
|
-
|
-
|
|
| |
Circuit/System Description
The headlamp switch is supplied with ground at all times. When
the headlamp switch is placed in either the park or low beam
position, ground is applied to the tail lamp signal circuit to the
body control module (BCM). The BCM sends this message to the
trailer lighting converter. The trailer lighting converter then
applies a voltage to the appropriate trailer tail lamp through
their respective voltage supply circuits.
Conditions for Running the DTC
B3885 02, B3885 04, B3886 02 and B3886 04
The appropriate trailer tail lamp signal is active
Conditions for Setting the DTC
B3885 02 or B3886 02
The trailer lighting converter detects a short to ground on the
control circuit.
B3885 04 or B3886 04
The trailer lighting converter detects an open control circuit.
Conditions for Clearing the DTC
The condition for setting the DTC is not longer present.
Action Taken When the DTC Sets
The appropriate trailer tail lamp is inoperative.
Reference Information
Schematic Reference
Trailer Connector/Provision 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
Circuit/System Verification
Ignition ON, perform the appropriate Trailer Tail Lamp test. The
appropriate trailer tail lamp should be ON/OFF.
Circuit/System Testing
Trailer Tail Lamp Malfunction RPO VQ9
| 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
5 |
| |
• |
X88 Trailer Connector terminal
7 |
| 3. |
Command the Trailer Tail Lamps
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 tail lamp circuit at the
trailer. |
Trailer Tail Lamp Malfunction RPO D8G
| 1. |
Ignition OFF, remove the
appropriate bulb and inspect. |
| ⇒ |
If bulb is faulty, replace bulb. |
| 2. |
Ignition OFF, remove the
harness connector of the appropriate component listed below:
|
| |
• |
E7L License Plate Lamp -
Left |
| |
• |
E7R License Plate Lamp -
Right |
| 3. |
Test for less than 5 Ω
between the ground circuit harness connector wiring color WH and
ground. |
| ⇒ |
If greater than the specified value, test the
appropriate ground circuit for an open/high resistance. |
| 4. |
Connect a test lamp between
the appropriate control circuit terminal listed below and
ground: |
| |
• |
E5E Tail Lamp - Left wiring
color BK |
| |
• |
E5F Tail Lamp - Right wiring
color BK |
| |
• |
E7L License Plate Lamp - Left
wiring color BK |
| |
• |
E7R License Plate Lamp - Right
wiring color BK |
| 5. |
Command the Trailer Tail Lamps
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. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
Control Module References for trailer lighting converter
replacement, setup and programming
|
