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need some help with overheating

Check ECU wiring next. Do both small relays have the 12V in the small pins? The fans are capable of running (jumper wires demonstrate that), the relays just do not turn on.
 
ok i checked the the fan relays and they have 12v in the small pins. so use a odb2 reader to check the ecu wiring? or is there another method?
 
oh yea by the way was at the junkyard today and looked at three different contours and they all have different fuse boxes then me, and i see the three 60amp fuses bolted, and mine aren't. but the green relay "low fan iirc" the relay is twice and big as mine. so i grabed it and the high speed just because, to plug them in and give them a try.
 
The OBD2 reader will pull codes, might be worth doing. The wiring I refer to is from the relay to the ECU itself. You would need to access the ECU plug check from there to the relay socket. Need pinout diagrams to do that, which I might be able to provide later.
 
More diagrams

More diagrams

Later is here:)

Low speed relay base:
lowspeedrly.gif


High speed relay base:
highspeed.gif


PCM Plug and list of pins:
BIGPCM421.gif


Battery Relay Box:

BJB.gif
 
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haha wow yea more then my knowledge. I'm trying to figure it out but so lost.

Wanna just tell me which pin i need to check? lol

by the way my fuse box doesn't look like that. and the relay i did get today from another tour is larger then mine.
 
I got all the diagrams from Alldatadiy.com, service manuals online. The ECU plug hopefully is the same. Maybe you need a Ford service CD for 2000. The circuits will be similar. The ECU pin 45 "91S-PA7" leads to low speed relay pin, pin 19 "91S-PA17" leads to High speed relay pin. It may help to print the diagrams and draw lines with highliter pen, takes a lot of concentration to diagnose a car electrical problem (it's more like TV or computer repair!)
 
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alright, i'll see if i can find the service cd for mine.
but quick question. the ecu is where? i haven't really torn the car apart like i did my pgt.
is it behind the amp for the radio? i looked behind the glovebox from underneath and it looks like that is the ecu , but i can't find out how to release it.
 
oh yea and also am i just using my voltmeter on the pin spot? to see if power is being sent? or how am i going to check this....man i'm such a noob
 
if you open the hood, at the very corner on the passanger side, between you inner fender and the firewall you will see a small tank for your power steering pump. lift it up slightly and below you will see a bolt right in the middle of a big long plud. unscrew that bolt and the wiring harnes of the ECU will come out.
the ECU you remove from inside of the car (behind the glove box) and is held in there by a small plastic clip and some slide on (rail) retainers, but i dont think you need to remove the ECU...

these relays you got from the junk yeard, dont olug them if they are different part number. they shouldnt even fit in there. but i dont think it is a good idea to try them, even if they fit in the sockets.

and correct me if i am wrong, but if your fans are working with the jumper wire test, and you have 12v coming to the pins, and if with engine on you unplug the ECT sensor wires and fans are not coming on...there should be something wrong either between ECT -> ECU, or ECU -> Fuse Box communication lines.
why dont you just get the same new relays from a junk yeard and change them to rule them out 100%. I know you tested them, but...i also tested mine last week, worked fine and my car was still overheating...
 
well i am going to test the pin output, but the thing is even the 2000 contour at that yard, had the different style fusebox. and twice as tall low fan relay. i'll look at the part numbers tonite and see if they match up.
I'm afraid even if i bought new relays from somewhere they won't be like mine.
 
What to measure

What to measure

You should set meter on OHMS, put one lead on the desired ECU plug other on the matching relay socket. Ohms reading less than 1 is good. Might need some small jumper clips.
 
OK let's reset and keep it simple.

The fan is supposed to come on whenever the A/C is operating. It's needed to blow air over the condensor. If the fan doesn't come on with the A/C the problem is not with the cooling system or any temperature sensors. So stop looking there and changing parts etc.

If shorting across the relay pins causes the fans to work the high current wiring, fuses and fan and fan resistor are working.

That isolates the problem to the ECU (computer), wire from the ECU to the relay, ground wire from the relay socket to ground or slight possibility that the relay is operating but the contacts not closing.

With the car running have someone turn the A/C on and off while you put your finger on the relay to feel for the click. If you don't feel the click pull the relay and measure the control pin for 12 volts. If no 12 volts it's the ECU or the wire from the ecu to the relay box. If you have 12 volts on the control pin check for continuity from the ground pin to the battery negative.

My guess is it's the ground wire on the relay unless you've pulled the ecu for any reason in the past then it's most likely a bad pin on the ecu.
 
ok........
1.neither fan comes on at any point in time, ever. so car overheats.
2.if you read, i already started the car without the relay and there is 12v's present to the small pin on both low and high fan relays.

i don't know where the ground wire from the relay goes, as i don't have the same fusebox as anybody else so far. if you would take some pictures to show me which ground wire and where it leads i'll gladly check.

but the fact still remains the car over heats because the fans don't spin.so i need to get the fans spinning.
 
alright this is the difference between the relays. my thing is why are they different?? the high speed fan relay is the same, but the lows are different.

dsc02275mediumvv7.jpg


junkyard relay part number
dsc02281mediumuw4.jpg


my original relay
dsc02283mediumul0.jpg


so for some odd reason do i just have the wrong relay? i just don't see why there would be such a big difference
 
You want to see if the wire is solid from the ECU to the relay socket. One probe at the desired pin of the ECU and one in the small relay socket pin (not 12V one), is it less than 1 ohm. The ground is what the ECU provides when it turns on the fan relay. Is there a trustworthy repair shop in your area?
 
im sure there is a few, but i don't few like spending a few hundered bucks to fix this.

i'll check the ohm thing hopefully today maybe tomorrow.
and also this weekend, i started it up and let it sit there and it never got above 1/2 way on the gauge it was little below half way. and it never once over heated i drove it around a little bit.

but still worries me since the fans don't turn on with the a/c
 
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