2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 628
* With X88 - Terminal A
* With Z88 - Terminal B
瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.
7. Connect the harness connector at the headlamp.
8. Connect a 20 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the headlamp is activated.
瀚慖f the headlamp does not activate and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests
normal, test or replace the headlamp.
瀚慖f the headlamp does not activate and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test
or replace the headlamp.
9. Connect a test lamp between the B+ circuit terminal 85 and the control circuit terminal 86.
10. Command the Low Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded
states.
瀚慖f the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
瀚慖f the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace
the BCM.
11. If all circuits test normal, test or replace the low beam headlamp relay.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Relay Replacement (Attached to Wire Harness) (See: Power and Ground Distribution/Power Distribution Relay/Service and Repair/Relay
Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (See: Power and Ground Distribution/Power
Distribution Relay/Service and Repair/Relay Replacement (Within an Electrical Center))
* Headlamp Replacement (Cadillac Escalade) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp
Replacement (Cadillac Escalade))Headlamp Replacement (GMC Yukon Two-mode Hybrid) (See: Lighting and Horns/Headlamp/Service
and Repair/Removal and Replacement/Headlamp Replacement (GMC Yukon Two-mode Hybrid))Headlamp Replacement (Yukon) (See:
Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement (Yukon))Headlamp Replacement
(Chevrolet Tahoe Two-mode Hybrid) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp
Replacement (Chevrolet Tahoe Two-mode Hybrid))Headlamp Replacement (Tahoe, Avalanche) (See: Lighting and
Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement (Tahoe, Avalanche))Headlamp Replacement
(Escalade PLATINUM) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement
(Escalade Platinum))Headlamp Replacement (Non HID) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and
Replacement/Headlamp Replacement (Non HID))
* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM replacement, setup, and programming
B2580
DTC B2580
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B2580 00
- Headlamp High Beam Control Circuit
Diagnostic Fault Information
