What does it mean?
U1152 is a Network (CAN bus, module communications) fault code. It indicates: No Communication With HVAC Control Module .
Symptoms
- Climate control display blank, frozen or not responding to any button
- Blower stuck on one speed or not running at all
- Air coming out at the wrong temperature or from the wrong vents because the blend and mode flaps no longer move
- Air conditioning compressor not engaging
- Rear or dual zone controls dead while the rest of the dash works
- The climate module missing from the scan tool module list
Likely causes
- Loose or corroded connector at the back of the climate control head
- Blown fuse or an open supply to the climate control module
- Poor ground for the module behind the instrument panel or centre console
- Water damage from a blocked evaporator drain or a leaking windscreen seal soaking the dash harness
- Open or shorted bus wiring between the climate module and the body control module
- Internal failure of the climate control head, sometimes after a spilled drink
- Weak battery or a supply voltage that collapses during cranking
How to fix it
- Scan all modules and note whether the climate module is the only one missing
- Check the fuse feeding the climate module and measure supply voltage and ground at its connector under load
- Remove the connector and inspect for corrosion, moisture, bent pins and heat damage
- Look for water in the passenger footwell and check the air conditioning drain, since a blocked drain regularly kills this module
- Measure the bus lines at the module connector and compare them with a communicating module
- Test wiring between the climate module and the body control module for opens and shorts
- Replace the climate control head only after wiring, supply and water intrusion have been ruled out, then perform any required flap calibration