I have a 03 mustang, just can’t figure out what the issue is on why my radiator fan isn’t working. I have checked the 50A fuse, replaced the coolant temperature sensor and I still haven’t found the solution. when I turn the car ac on it blows warm, but clicks over like it wants to turn the fan on. car doesn’t overheat and remains “normal” temperature when running for awhile. HELP
03 MUSTANG RADIATOR FAN NOT WORKING
- Thread starter JaedonMustang03
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Hands down. The EASIEST way to trouble shoot a cooling fan "issue" is to use an ODB2 scanner with bi-directional controls to "command" the fan to run. This offers an easy way to see what is happening by testing for voltage at various points. Create an attack plan based upon what works (high/low speed) and what does not work.
Further. The ODB2 scanner route offers an easy way to find out what the PCM "thinks" the ECT value is as well as what the PCM is commanding the fan to do based upon that value.
Want to know if the ECT is accurate? Then check the ECT after a cold soak. Does it match the outdoor temperature?
Here's some information on an affordable Windows based unit with bi-directional controls. Very advanced graphing capabilities.
ForScan ODB2 scanner w ELM327 USB
www.stangnet.com
If pressing the "easy" button is not for you, the use a test light to find out IF there is power at the fan connector with the AC on. IF there's no power at either of the fan's hot wires it will be necessary to trouble shoot the fan's low speed power circuit.
Next disconnect the fan connector and jump +12 volts from the battery towards the fan using scrape wire. Does the fan work on BOTH speeds? IF not, then the fan is bad. Best to use a fused jumper if you have it.
I always recommend starting every electrical trouble shooting session with a through review of the battery, charging system, and grounds.
Howto perform charging system voltage drop test
www.stangnet.com
Further. The ODB2 scanner route offers an easy way to find out what the PCM "thinks" the ECT value is as well as what the PCM is commanding the fan to do based upon that value.
Want to know if the ECT is accurate? Then check the ECT after a cold soak. Does it match the outdoor temperature?
Here's some information on an affordable Windows based unit with bi-directional controls. Very advanced graphing capabilities.
ForScan ODB2 scanner w ELM327 USB
ForScan ODB2 scanner w ELM327 USB
While working on your car have you ever wanted: to find an ODB2 operational PID value (say fuel pressure or MAF)? How about graph a PID value over time? Or compare multiple PID's over time? Access a bi-directional PCM control such as test a...
www.stangnet.com
If pressing the "easy" button is not for you, the use a test light to find out IF there is power at the fan connector with the AC on. IF there's no power at either of the fan's hot wires it will be necessary to trouble shoot the fan's low speed power circuit.
Next disconnect the fan connector and jump +12 volts from the battery towards the fan using scrape wire. Does the fan work on BOTH speeds? IF not, then the fan is bad. Best to use a fused jumper if you have it.
I always recommend starting every electrical trouble shooting session with a through review of the battery, charging system, and grounds.
Howto perform charging system voltage drop test
Howto perform charging system voltage drop test
To anyone else reading any of my posts I usually include the line: Today's cars simply will not run right without a strong battery and charging system! Cut corners here at your own risk I'm a big believer in starting with the basics. As such I...
www.stangnet.com
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