Software Incompatibility With Auxiliary Heater Control Module

What does U0325 mean?

U0325 stands for Software Incompatibility With Auxiliary Heater Control Module. Two or more of the car's computer modules are not communicating properly over the vehicle network (CAN bus).

Network codes cover the communication between the car's computer modules. When the car's computer sees a reading outside its normal range, it stores this code and may turn on a warning light on the dashboard.

Common causes

• Low or weak battery
• Damaged network wiring or connector
• A module that has lost power or failed
• Aftermarket accessories interfering with the network

What to do

1. Read all stored and pending codes with a scanner. Several codes together often point to one cause.
2. Note the freeze frame data (speed, temperature, load) recorded when the code was set.
3. Inspect the wiring and connectors of the part named in the code for damage, corrosion or looseness.
4. Fix the most likely and cheapest cause first, then clear the code and drive to see if it comes back.

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Frequently asked questions

What does U0325 mean?

U0325 means “Software Incompatibility With Auxiliary Heater Control Module”. It belongs to the network communication group: Two or more of the car's computer modules are not communicating properly over the vehicle network (CAN bus).

Is it safe to drive with U0325?

You can usually drive carefully for a short time, but fix it soon to avoid further damage or higher fuel use.

How do I clear U0325?

Fix the cause, then clear the code with an OBD2 scanner or app. If the fault is still there, the code will come back.

Related codes

• U0321Software Incompatibility With Suspension Control Module
• U0322Software Incompatibility With Body Control Module
• U0323Software Incompatibility With Instrument Panel Control Module
• U0324Software Incompatibility With HVAC Control Module
• U0326Software Incompatibility With Vehicle Immobilizer Control Module
• U0327Software Incompatibility With Vehicle Security Control Module
• U0328Software Incompatibility With Steering Angle Sensor Module
• U0329Software Incompatibility With Steering Column Control Module

Code meanings can vary by manufacturer. This page is general guidance, not a repair manual. Always confirm the cause before replacing parts.