Chesapeake

I was checking to see if these trucks come with a fuel filter heater and if so where is it located and how do you tell if it is working?

Thanks,

Mechanos

On your '01, it is located in the fuel filter canister. You would go about checking it with a multi meter.

Chesapeake

Do you by any chance have any photos of where it is located? Also where do I place the probes? Does the truck have to be cold or can the engine be warm? Sorry about this but I am really a novice when it comes to electrical!

gmctd

It's the large black connector down by the WIF drain lever - it works only from below 40*F up to ~85*F - it will not turn on at 50*, or 40* or etc* - ambient and fuel temps must be below the low setpoint

Check the fuse in the fuseblock - the red or yellow wire is hot, black is ground - the heater will test as open if ambient temps are above the low-temp setpoint, making it difficult to verify unless you're outside under the hood and freezing..............

Mechanos

Pull the connector off the heater. Turn the key on, you should see 12V. If you don't, check for bad grounds, blown fuse and also check the fuel heater relay in the PDC. There is also a temp sensor in the heater that will only energize the heater element when the fuel temp. is below 45°F +/- 8° and then turns the heater element off once the fuel temp. reaches 75°F +/-8°.

Chesapeake

Thank you for all the help and the diagram. What is the PDC? When I pull the wire connector to check for 12V and turn the ignition on does the outside temp have to be 45 degrees or below or should there be power going there at all times?

Thanks

gmctd

The connector is always powered with IGN on - the temperature switch is in the heater module - again, the switch does not turn on until ambient\fuel temp is below the setpoint - the switch is not serviced separately from the heater - gotsta replace the heater module if the switch is bad - never heard of one going bad unless the owner had lotsa problems with WIF

Mechanos

PDC = Power Distribution Center (big fuse/relay box on the driver's inner fender... right by the battery).

Chesapeake

Thanks for the help. I will take a look at everything tonight or tomorrow morning. The reason I am checking this is because I have had a gelling issue this winter. I add power service every time I fill up but still gel. The reason I believe it was a gelling issue is because I just had a Brand new FASS DDRP and also a low fuel pressure light on and then one day when the temps were around 2 degrees in the morning I started out and after a few moments my light came on and my truck would barely make it home. Luckly I was close. So I'm just checking to see if it is a fuel problem or if my fuel filter heater is not working.