2 speed fan KOEO test

SCarSC

Registered User
I ran the KOEO test this morning, I can hear the clicks and what i assume is the low speed fan coming on...then it shuts off, more clicks and no high speed fan...would this indicate that the motor is bad or is it possible that there is another reason for the high speed fan to not work in this test.

I can pull the eec ground at the battery and the fan will come on...I can pull the wire from the temp sensor on the pass side and the fan will come on...this is just the low speed fan correct?

also, i dont currently have a chin spoiler...i should probably do something about that, but I am having issues with the car running warm...just did change the water pump and thermostat following a BHJ balancer install...its possible that i dont have all of the air out of the coolant system yet...proper procedure for that is a few heating and cooling cycles and opening the bleeder bolt right? thermostat is a 197 motorcraft with the bleeder hole at the 12 oclock position.

I suppose i am just typing things out now to get them out of my head...any feedback would be appreciated.
 
Can you volt check both hot leads to the fan motor and then repeat the KOEO test? Do you have a spare IRCM you can test with?

The factory chin spoiler helps create a negative pressure zone below/behind the engine at speed. Do what you can to replace/repair it.
 
Crude but effective...one can undo the 3 terminal plug near the fan motor...one is ground and I believe it's obvious because it is black. The other 2 are low speed and high speed. These motors have 2 distinct separate windings, low and high, so you can test with 12 volts to one hot lead and then the next. From experience use a decent size wire, like 12-14 gauge(it gets hot if smaller).
Like I said crude but very effective to see if both windings are ok.( make sure it's grounded or use a lead off the battery negative side)
 
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I do not have a spare IRCM currently...i was going to buy one and havent yet. Once it gets hot the low speed will come on automatically...would that indicate that the IRCM is working correctly...or that it is only working correctly for that speed?

I dont have very much knowledge when it comes to electrical things really...dont have a volt meter, if i picked one up would i just put one probe on the male end and one on the female to check for continuity?


les, as far as jumping the fan from the battery, I dont have any spare wires laying around...apart from a nice metal clothes hanger...probably need to make another trip to the hardware store.
 
There are codes for hi speed fan failure:

83 O High Speed Electro Fan drive circuit failure (3.8L SC only)
88 O Electro Drive Fan circuit failure (3.8L SC only)

....what codes are you seeing?

If no codes, you might want to focus on the IRCM instead of the fan motor.

If you don't actually have a code reader see if a local repair shop or auto parts store will read them for you. If you don't/can't, order one off the 'net - they should be around $35 and up. It will be handy in the future.

If you don't have skills or testing tools, etc., you may need to start throwing new/used parts at it, I think, instead - that or use this as an excuse to acquire both.
 
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A digital meter would come in handy. Not difficult to operate and these days you can pretty inexpensive ones.

I just bought a Ford Code reader with display from Jegs, $28 bucks and shipping if needed(makes me ill I paid well over $50 for the one I had but that was 8-9 years ago). I lost the one I had or it's still packed so good I will never find it.

INNOVA 3145 for our vehicles they have 5 or 6 left on Ebay and probably on their site. Comes with the book for Ford codes and how to use it.

http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&itemPerPage=60&Ne=1%2B2%2B3%2B13%2B1147708&searchTerm=INNOVA+3145
 
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codes

i believe they were 23 and 85...23 appears to be related to tps and 85 was about running lean...I just replaced the 30lb injectors with 36lbers...late model sc and plenum 10% pulley and put a larger intake on...my assumption is that without a tune im going to get some codes.
 
Dumb question(nothing to do with the fan) but did you put in a non Ford mass air flow sensor for 36lb injectors?

The 94-95 Ford MAF will do squat( as well as the 89-93's) because the EEC really doesn't read the read the Ford ones for injector size and it assume 30lb injectors without a chip to tell it's 36.
 
Great it's probably a 36lb sampling tube they are different colors for different injector sizes, of course I have no idea what the colors are, maybe orange for 36 and 38lb injectors?
 
honestly i cant remember right now what the sampler tube coloring is...but i am almost positive it is not correct...might be for 42lb injectors...but i thought i read somewhere that with a tune from dalke the sampling tube wasnt really an issue as long as he knew the modifications involved...i could be wrong and need to purchase the correct tube.
 
I think but not sure if Dave can correct for that most likely he can. It's getting harder to get C&L sampling tubes since they closed their doors. I think Bill at SC Performance had a couple of sampling tubes left and maybe even Dave does.
 
I may be wrong but my code testing has always triggered one fan speed to come on and that is at initial code scanning.

I currently am running rich and the codes are 171,172,173,179 and 188.

Paul
 
I have read elsewhere that the koeo test should start both speeds of the fan...perhaps i have read incorrectly...

either way, i hooked the lines up to the battery with jumper cables and paperclips...both speeds work that way...does that point to the IRCM then?

also, i have reattached the air dam/chin spoiler...was going to drive it in to work today, but i messed with the lower control arm camber setting and clearly got it all wrong. fix that tomorrow and drive it i suppose.

does anyone have a link or part number to the proper strut rod bushings/washers...i purchased some on rock auto and they are clearly too large and now im squeaking.
 
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from the codes that I read I dont believe that I have anything related to the high speed fan...im going to try to pick up an IRCM soon, see if that fixes the problem or not.
 
Lame resolution...well at least I think it is resolved...I had unbolted the ircm and laid it down to make room for my air filter...moved stuff around and put the ircm back in, grounding it properly in the process, and now I hear both speeds with Koeo. Anyways, I have been loading up on replacement parts and tools as a result so that's good I suppose...thanks for the ideas.
 
...that, or you managed to encourage a stuck relay to start cooperating :)

But yes, grounds/connections are critical with these cars.

Thanks for the update and good luck w/it.
 
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