HVAC Control Module Lost Communication With Coolant Heater Control Module On LIN Bus
Table of contents
U1525 CADILLAC Possible Causes
- Faulty Coolant Heater Control Module
- Coolant Heater Control Module harness is open or shorted
- Coolant Heater Control Module circuit poor electrical connection
- Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module
How do I fix code U1525 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 U1525 CADILLAC code
The cost of diagnosing the U1525 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)
U1525 CADILLAC Description
The Local Interconnect Network (LIN) Bus consists of a single wire with a transmission rate of 10.417 Kbit/s. The serial data is transmitted over a LIN circuit between a master control module and other LIN devices within a particular subsystem. If serial data communication is lost between any of the LIN devices on the LIN bus network, the master control module will set a no communication code against the non-communicating LIN device. The Diagnostic Trouble Code (DTC) will set when a supervised periodic message to the Heating, Ventilation, and Air Conditioning (HVAC) Control Module from the Coolant Heater Control Module has not been received.