Lost Communication With Hybrid Powertrain Control Module On Chassis Expansion CAN Bus
Table of contents
U18B5 CADILLAC Possible Causes
- Faulty Hybrid Powertrain Control Module
- Hybrid Powertrain Control Module harness is open or shorted
- Hybrid Powertrain Control Module circuit poor electrical connection
How do I fix code U18B5 CADILLAC?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Cost of diagnosing the U18B5 CADILLAC code
The cost of diagnosing the U18B5 CADILLAC code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
U18B5 CADILLAC Description
Devices connected to the Chassis high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices. The devices have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver device as an availability indication of the transmitter device. Each message contains the identification number of the transmitter device.
The Motor Control Modules and the Hybrid Powertrain Control Module 1 are all internal to the Power Inverter Module. Communication diagnostics for the serial data, including device power and ground as well as the wakeup circuits for Motor Control Modules and the Hybrid Powertrain Control Module 1 are all diagnosed from external sources only to the Power Inverter Module connector because any circuit fault condition within the Power Inverter Module will cause a complete replacement.The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.