DTC B260B or B260C
Diagnostic Instructions
DTC Descriptors
| DTC B260B 02: Left Daytime Running Lamp Relay
Control Circuit Short to Ground |
| DTC B260B 04: Left Daytime Running Lamp Relay
Control Circuit Open |
| DTC B260C 02: Right Daytime Running Lamp Relay
Control Circuit Short to Ground |
| DTC B260C 04: Right Daytime Running Lamp Relay
Control Circuit Open |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Ambient Light/Sunload Sensor Signal
|
B2645 03*
|
B2645 07*
|
B2645 07**
|
-
|
Left Daytime Running Lamp Relay Control
|
B260B 02*
|
B260B 04**
|
1
|
-
|
Right Daytime Running Lamp Relay Control
|
B260C 02*
|
B260C 04**
|
1
|
-
|
Left Daytime Running Lamp Control
|
1
|
1
|
2
|
-
|
Right Daytime Running Lamp Control
|
1
|
1
|
2
|
-
|
Ambient Light/Sunload Sensor Ground
|
-
|
B2645 07
|
-
|
-
|
1. Daytime Running Lamps (DRL) inoperative
2. Daytime Running Lamps (DRL) always ON
* Daytime Running Lamps (DRL) inoperative
** Daytime Running Lamps (DRL) always ON
|
|
| |
Circuit/System Description
Daytime Running Lamps (DRL) Without High Intensity Discharge
(HID) Headlamps RPO T4A
The body control module (BCM) receives a signal from the ambient
light/sunload sensor indicating a low or high ambient outside light
level. Under daylight conditions the BCM grounds the daytime
running lamps relay control circuit energizing the daytime running
lamp relay left and daytime running lamp relay right. The now
closed relay supplies voltage to the day time running lamps. If the
headlamps are illuminated the DRL will not illuminate.
Daytime Running Lamps (DRL) With High Intensity Discharge (HID)
Headlamps RPO T4F/T95
The body control module (BCM) receives a signal from the ambient
light/sunload sensor indicating a low or high ambient outside light
level. Under daylight conditions the BCM supplies a battery voltage
to the DRL.
Conditions for Running the DTC
| • |
Headlamp switch in AUTO
position. |
| • |
The ambient light is
day. |
Conditions for Setting the DTC
B260B 02 or B260C 02
The BCM detects a short to ground on the control circuit.
B260B 04 or B260C 04
The BCM detects an open control circuit.
Action Taken When the DTC Sets
The appropriate DRL is inoperative.
Conditions for Clearing the DTC
The condition for setting the DTC is no longer present.
Reference Information
Schematic Reference
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
DRL Malfunction - without HID Headlamps RPO T4A
| 1. |
Ignition OFF, disconnect the
appropriate daytime running lamp relay. |
| 2. |
Ignition ON, verify that a
test lamp does not illuminate between the control circuit terminal
87 and ground. |
| ⇒ |
If the test lamp illuminates, test the control
circuit for a short to voltage. |
| 3. |
Verify that a test lamp
illuminates between the B+ circuit terminal 86 and ground.
|
| ⇒ |
If the test lamp does not illuminate, test the B+
circuit for a short to ground or an open/high resistance. |
| 4. |
Headlamp switch in HEADLIGHTS
position. Verify that a test lamp illuminates between the B+
circuit terminal 30 and ground. |
| ⇒ |
If the test lamp does not illuminate, test the B+
circuit for an open/high resistance. |
| 5. |
Connect a test lamp between
the appropriate daytime running lamp relay B+ circuit terminal 86
and the control circuit terminal 85. |
| 6. |
Engine running, headlamp
switch in the AUTOMATIC LIGHT position. |
| 7. |
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. |
| 8. |
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. |
| 9. |
Ignition OFF, disconnect the
harness connector at the appropriate headlamp. |
| 10. |
Connect a 10 A fused jumper
wire between the B+ circuit terminal 30 and the control circuit
terminal 87. |
| 11. |
Ignition ON, verify that a
test lamp illuminates between the control circuit terminal 9 of the
appropriate headlamp and ground. |
| ⇒ |
If the test lamp does not illuminate, test the
control circuit for a short to ground or an open/high
resistance. |
| 12. |
Ignition OFF, disconnect the
negative terminal of the C1 Battery. |
| 13. |
Test for less than 5 Ω
between the appropriate headlamp ground circuit harness connector
terminal 1 and ground. |
| ⇒ |
If greater than the specified value, test the
ground circuit for an open/high resistance. |
| 14. |
Reconnect the negative
terminal to the C1 Battery. |
| 15. |
If all circuits test normal,
test or replace the appropriate inoperative daytime running lamp or
relay. |
DRL Malfunction - with HID Headlamps RPO T95/T4F
| 1. |
Ignition OFF, disconnect the
harness connector of the appropriate inoperative headlamp.
|
| 2. |
Disconnect the negative
terminal of the C1 Battery. |
| 3. |
Test for less than 5 Ω
between the appropriate headlamp ground circuit harness connector
terminal 1 and ground. |
| ⇒ |
If greater than the specified value, test the
ground circuit for an open/high resistance. |
| 4. |
Reconnect the negative
terminal to the C1 Battery. |
| 5. |
Connect a test lamp between
the control circuit terminal 4 and ground. |
| 6. |
Command the appropriate Front
Park Lamp/Daytime Running Lamp test ON and OFF 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 control
circuit for a short to voltage. If the circuit tests normal,
replace the K9 Body Control Module. |
| ⇒ |
If the test lamp is always OFF, test the control
circuit for a short to ground or an open/high resistance. If the
circuit tests normal, replace the K9 Body Control Module. |
| 7. |
If all circuits test normal,
test or replace the appropriate inoperative daytime running
lamp. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
