Auxiliary Heater Temperature Command Circuit
Table of contents
B048D GMC Possible Causes
- Faulty Electrical Auxiliary Heater
- Electrical Auxiliary Heater harness is open or shorted
- Electrical Auxiliary Heater circuit poor electrical connection
- Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module
How do I fix code B048D GMC?
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.
Tech Notes
- DTC B048D 01: Auxiliary Heater Temperature Command Circuit Short to Battery
- DTC B048D 06: Auxiliary Heater Temperature Command Circuit Low Voltage/Open
Cost of diagnosing the B048D GMC code
The cost of diagnosing the B048D GMC 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)
B048D GMC Description
The Heating, Ventilation, and Air Conditioning (HVAC) Control Module sends a Pulse Width Modulation (PWM) signal to the electrical auxiliary heater, if the interior temperature is too low and additional heat is requested. The request signal from the HVAC control module, battery positive, ignition and ground circuits enable the electrical auxiliary heater to operate. Through the signal circuit the electrical auxiliary heater sends via a PWM signal the current status to the HVAC control module.