B0418 on 2013-2019 Cadillac XTS — Right Temperature Control Circuit (HVAC actuator circuit)
1 vehicles · 1 makes · $120-$450 repair
Most Reported On
B0418 is an OBD-II diagnostic trouble code meaning “Right Temperature Control Circuit (HVAC actuator circuit).” Body/climate-control code, seen most often on GM vehicles (Chevrolet, Cadillac, GMC) and also used in Saab automatic climate control diagnostics. It reports a fault in the circuit for the right-side (passenger) temperature control actuator — the blend door motor that mixes hot and cold air for that side of the cabin. Sub-codes narrow the failure mode: B0418:01 short to battery, B0418:02 short to ground, B0418:04 open circuit. Typical symptoms are a passenger side stuck hot or cold, no independent dual-zone control, or a clicking noise behind the dash. It is a comfort fault, not a safety or driveability one. This code is most commonly reported on 2013-2019 Cadillac XTS, with repair costs ranging from $120 to $450.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
This is a body code. A basic engine-code reader will not show it — you need a scanner that reads body modules. These read B0418.
One caveat that applies to every scanner: only powertrain codes are standardised across manufacturers. Body, chassis and network coverage is "enhanced" diagnostics, and how deep it goes varies by make and model year — check your specific vehicle against the tool's coverage list before buying.
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What you can do yourself, and what needs a shop
Reading the code, clearing it, and watching whether it returns is a driveway job with the right scanner. These steps are not:
- Module programming or software updates — needs the manufacturer software or a J2534 pass-through with a paid subscription.
- Replacing a control module — most are VIN-programmed and immobilizer-registered, so a new one does nothing until it is coded to your car.
- Airbag/SRS component work — a stored fault can deploy a live device.
If the vehicle is still under warranty, check for an open recall or technical service bulletin before buying anything — the repair may already be covered.
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FAQ
What does B0418 mean?
B0418 stands for "Right Temperature Control Circuit (HVAC actuator circuit)." Body/climate-control code, seen most often on GM vehicles (Chevrolet, Cadillac, GMC) and also used in Saab automatic climate control diagnostics. It reports a fault in the circuit for the right-side (passenger) temperature control actuator — the blend door motor that mixes hot and cold air for that side of the cabin. Sub-codes narrow the failure mode: B0418:01 short to battery, B0418:02 short to ground, B0418:04 open circuit. Typical symptoms are a passenger side stuck hot or cold, no independent dual-zone control, or a clicking noise behind the dash. It is a comfort fault, not a safety or driveability one.
What are the most common causes of B0418?
The most common causes of B0418 are: Failed right/passenger temperature blend door actuator motor, Broken or jammed blend door or stripped actuator gears, Open, shorted, or chafed wiring in the actuator circuit, Corroded or loose actuator connector, HVAC control module (or body control module) fault, Blown fuse feeding the HVAC actuator circuit. The specific cause varies by vehicle.
How much does it cost to fix B0418?
Repair costs for B0418 range from $120 to $450, depending on the vehicle and root cause.
Which vehicles are affected by B0418?
Au7o has documented B0418 across 1 vehicle models from 1 manufacturers: Cadillac.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.