DTC B259A or B259B
Diagnostic Instructions
DTC Descriptors
| DTC B259A 01: Left Cornering Lamp Relay
Control Circuit Short to Battery |
| DTC B259B 01: Right Cornering Lamp Relay
Control Circuit Short to Battery |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Left Cornering Lamp Relay Control Circuit
|
-
|
-
|
B259A 01
|
-
|
Right Cornering Lamp Relay Control Circuit
|
-
|
-
|
B259B 01
|
-
|
|
| |
Circuit/System Description
The daytime running lamp relay - left and daytime running lamp
relay - right is supplied with battery voltage at all times. If the
engine is running and the ambient light is day the body control
module (BCM) energizes the appropriate daytime running lamp relay
by applying ground to the appropriate daytime running lamp relay
control circuit. When the appropriate daytime running lamp relay is
energized, the relay switch contacts close and battery voltage is
applied through the appropriate daytime running lamp relay supply
voltage circuit which illuminates the appropriate daytime running
lamp.
Conditions for Running the DTC
| • |
Headlamp switch in AUTO
position. |
| • |
The ambient light is
day. |
Conditions for Setting the DTC
The BCM detects a short to voltage on the control circuit.
Action Taken When the DTC Sets
The daytime running lamps are always OFF.
Conditions for Clearing the DTC
The condition for setting the DTC is not longer present.
Reference Information
Schematic Reference
Headlights/Daytime Running Lights (DRL) 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
Engine is running idle, supply sufficient light to the ambient
light sensor to simulate daylight conditions. The daytime running
lamps should be ON.
Circuit/System Testing
| 1. |
Ignition OFF, disconnect the
appropriate daytime running lamp relay. |
| 2. |
Ignition ON, verify that a
test lamp illuminates between the B+ circuit terminal 86 and
ground. |
| ⇒ |
If the test lamp is OFF, test the B+ circuit for a
short to ground or an open/high resistance. If the circuit tests
normal, replace the K9 Body Control Module. |
| 4. |
Engine running, headlamp
switch in the AUTOMATIC LIGHT position. |
| 5. |
Connect a test lamp between
the appropriate daytime running lamp relay B+ circuit terminal 86
and the control circuit terminal 85. |
| 6. |
Cover the ambient light sensor
to simulate night conditions. The test lamp should be OFF.
|
| ⇒ |
If the test lamp is ON, test the control circuit
for a short to ground. If the circuit tests normal, replace the K9
Body Control Module. |
| 7. |
Supply sufficient light to the
ambient light sensor to simulate daylight conditions. The test lamp
should be ON. |
| ⇒ |
If the test lamp is OFF, test the control circuit
for a short to voltage or an open/high resistance. If the circuit
tests normal, replace the K9 Body Control Module. |
| 8. |
If all circuits test normal,
replace the appropriate daytime running lamp relay. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
