Jeep Wrangler - P0480: What is it? Causes and Diagnosis

OBDII Trouble Code P0480 can be a common code.  It indicates that your Jeep Wrangler’s “cooling fan 1 control circuit” is malfunctioning.  It’s a generic code, so it has the same meaning for any vehicle made for the 1996 model year and up.

P0480 Definition:  Cooling Fan 1 – Control Circuit Malfunction

Below is the Jeep Wrangler definition of "P0480", broken down into its main parts. 

Cooling Fan 1.

Electric cooling fans are now standard equipment in modern vehicles.  The PCM (powertrain controller module) activates them whenever the Wrangler is at a specific temperature.  When the air conditioner turns on, one of these lights will come on as well.

Control Circuit Malfunction

If the PCM has commanded cooling fan 1 to turn on, but there is an error, P0480 will be stored in the PCM’s memory.  This occurs if either the fan doesn’t respond or the PCM detects a serious fault in the control circuit.

Jeep Wrangler P0480 symptoms

The P0480 will not make your Wrangler drive differently.  The fan won't affect how the engine operates (unless it starts to heat up).  The engine might start to knock, misfire, or smoke if you heat it too much.

As stated above, driving your Wrangler without a functioning fan can cause it to overheat, particularly if you are driving on a hot day or you’re in heavy traffic.  This can cause your air conditioner not to work properly.

You’ll want to keep an eye on the temperature gauge and fix P0480 as soon as possible.  Overheating can cause a blow to the head gasket, which will require a more costly repair.

Jeep Wrangler - P0480 Diagnostics and Causes

Below are possible causes of P0480.  There are many possible causes for this code.  They are listed here in order of their potential causes.  

1. Look for other codes

It is possible to cross-reference other codes and gain useful insight.  You might be able to clear the P0480 code from your Jeep Wrangler if it is related to the engine temperature sensor.

2. Check Cooling Fan 1

The battery should be disconnected.  You don’t want the fan spinning up (which could happen if you try and spin it and the vehicle is hot).

Two Jeep Wrangler fans are better than one. NOT directly in front of your air conditioner Is nearly always fan 1.

You’re going to spin the fan to see if it’s locked up or otherwise bad.  Before you spin the fan make sure it is cold and unplugged.  If the engine gets too hot, fans will turn on automatically.

If the fan requires effort to spin, then it’s bad.  It should be replaced to fix the P0480 problem in your Jeep Wrangler.  Check the codes to see if it returns.

3. Examine the wiring harness at the fan

Check the wire harness connecting to the fan to make sure it is turning ok.  The road debris can cause damage to fan wiring by kicking it under your vehicle, ripping up the harness and damaging the wires.  If you live in an area that is chipmunk friendly, don’t be surprised if they chewed the wiring.  I’ve seen this a few times.

You must ensure that your terminals are securely connected to the fan.  Make sure that pins don't corrode and are straight.

4. Examine the Fuses and Fan Relay

Now that we have verified that nothing obvious is causing P0480, it’s time to take a look under your Wrangler’s hood at the fan relay.  Before you do, inspect the fan relay fuses to make sure that they haven’t been blown.  This can be done visually.  Check that power is flowing to the fan relay.

Now it’s time to take a look at fan relay 1 itself.  Check out the video below, it’ll show you how to test the fan relay with a multimeter.  If there’s no power going to the relay, you’ll need to find where the short is.

5. Others P0480 Reasons

Here are some other common causes of P0480, although they aren’t as common as the ones listed above:

• VSS = Vehicle Speed Sensor
• Failed Intake Air Temp Sensor
• The A/C Pressure Switch

Conclusion

The most common cause of P0480 is a bad fan/a bad relay.  We wish you the best with your Jeep Wrangler repair!