U1807

DTC U1807

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor
DTC U1807 00
- Battery Charger Control Module High Voltage Energy Communication Bus Off

Circuit/System Description

The high voltage energy management high speed GMLAN serial data circuits are serial data buses used to communicate information between the control modules. The high voltage energy high speed GMLAN serial data circuits also connect directly to the auxiliary data connector. If this serial data system is inoperative the control modules will still communicate with the scan tool due to other serial data systems but not with each other.

Conditions for Running the DTC

* Supply voltage to the control modules are in the normal operating range.
* The vehicle power mode requires serial data communications.

Conditions for Setting the DTC

The control module setting the DTC has attempted to establish communications on the powertrain high speed GMLAN serial data circuits more than 3 times.

Action Taken When the DTC Sets

DTC U1807 is a type A DTC.

Conditions for Clearing the DTC

DTC U1807 is a type A DTC.

Circuit/System Verification

Verify that U007A is not set.

If the DTC is set, refer to DTC U007A U007A.