P2B2F: Fan 1 Performance/Stuck Off
What to do
Watch the temperature gauge in traffic, and be ready to pull over safely if it climbs. This fault shows itself when you stop, not when you drive — there is plenty of airflow at speed and none at a standstill, which is why it catches people out in queues.
If the air conditioning has also gone weak in traffic while working fine on the move, mention it. That is the same fault, not a second one — the fan cools the air conditioning condenser too.
Ask for the shroud to be checked for leaves and debris before the fan is replaced. It is a common cause and costs nothing.
Mention whether the fan runs at all, and whether it sounds like it is running slowly. A fan that works at one speed but not another usually means the control module rather than the motor.
What this code means
The first cooling fan is being commanded but not running, or not reaching the speed asked of it.
Performance separates this from a circuit code, and the distinction points somewhere specific. The wiring is intact and the command is going out — the module is judging the result and not finding it. Most modern vehicles measure fan speed directly, so this is a comparison rather than an inference.
Modern fans are variable-speed rather than switched, driven by a control module built into the shroud that takes a requested speed and delivers it. That architecture creates a diagnostic shortcut worth knowing: a fan that works at full speed but not at low speed, or the reverse, is almost always the control module rather than the motor. A failed motor does not work selectively.
Stuck off is the dangerous direction and it has two consequences, not one.
- The engine overheats in traffic, where there is no airflow without the fan. At speed it may seem perfectly fine, which is exactly why this gets ignored.
- The air conditioning condenser is not cooled either, so the system loses efficiency and its pressure climbs. Poor cooling in traffic with warm air from the vents is the same fault described twice.
Look for physical obstruction before anything electrical. Leaves, plastic bags and road debris pack into the shroud, and a motor working against that draws more current and eventually fails.
Likely causes
Start here
- Failed cooling fan motor · moderate
- Faulty cooling fan control module · moderate
- Debris obstructing the fan · easy
Less common
- Failed cooling fan relay · easy
- Blown cooling fan fuse · easy
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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