Jump to content
Server maintenance Read more... ×
DemonHunter

EL THERMO FAN ISSUES

Recommended Posts

Ok  l am at a complete and total bloody loss here big time with my stupid car, every time l turn  key to start the thermos come on an stay in when it’s running.  I was told it would be the ecu which l  changed an still does it . was also told oh it’s the bcm which l changed when  fitted a new el xr ecu an had to reprogram the ef bcm that was also replaced same thing fans came on an stayed on .  Then get told it would be the fans which were changed 4 times even did the ignition same thing so refitted the original el ecu an ef bcm  that was from the original Thor l built  then someone said oh it’s the temp sensor on the thermostat housing an yet same thing fans come on when key is turned an when it is running   .Funny thing is l even  unplugged it an yet no difference period Sonos lm completely lost at what it’s doing an it’s driving me frigging nuts   , lve now fitted Ef fans that the left one has the 3 wires an the other is stock but re-did the plug so l can hook em up like the originals but will be going  to fit a extra relay for the 3rd wire on the left fan

All relays have been replaced where the fans are and all next to the battery even checked the auto tx fuse an it’s fine as l take it out an fans won’t run so now l am almost ready to burn the thing down as lve just replaced the fuel tank pump an everything that sent me broke doing it lol

Share this post


Link to post
Share on other sites

Are the fans running Half speed, one full or both full speed, etc?

Have you checked for thermo relay fault codes?

 

If it's an EL ECU, and auto trans, have you done the diag mode thermo-fan speed/relay check?

Neutral to drive once = one high

Neutral to drive again = both low,

Neutral to drive a third time = both high

Cycle repeats

(note, EF ECU only does all on and all off with above check)

 

If you unplug the coolant temp sensor, the dash gauge will show full hot, and the fans will run flat out.

If the dash temp gauge reads accurate, the sensor is good, and hence won't be affecting the fans.

 

If you turn the A/C on, at high blower motor speed, this will force the thermo fans full speed also.

 

Share this post


Link to post
Share on other sites

The fans come on as soon as the ignition is on n both are on at low speed  , temp gauge shows cold  when temp sensor is unplugged I start it gauge goes to hot fans full bore , l do the 

Neutral to drive once = one high

Neutral to drive again = both low,

Neutral to drive a third time = both high and far as l can see an hear fans stay low speed so it’s got me beat 

 

Share this post


Link to post
Share on other sites

This is a wiring diagram, showing how EL thermo's are connected.

EL Falcon Thermatic Fan Wiring.pdf

 

The ECU has two thermo outputs - High and Low

 

When the LOW output is energised, BOTH Fans run on low

When the HIGH output is energised, only Fan 2 runs High speed

When both HIGH and LOW outputs are energised together, BOTH Fans run High Speed

 

Your Low output thermofan relay is being continuously energised, either by the ECU output,

or by some other means.

That is where you need to start looking.

 

Start by Unplugging just the ECU, turn the key to ignition, and see if the thermo's run or not.

 

That will tell you, if it's an ECU based issue (ECU plug wiring, internal or external sensor)

OR

If it's more likely a wiring issue in the engine bay.

 

Share this post


Link to post
Share on other sites

Glad this thread is here haha, my thermos have just started playing up.
Won’t switch to high speed when the car starts getting hot (like in slow traffic) fans stay on slow, which still stops it from over heating but it definitely heats up.
Hitting a/c doesn’t help, they cycle up and then shut off, presumably no gas in the a/c so it won’t let it run.

Share this post


Link to post
Share on other sites
1 hour ago, Defective said:

Glad this thread is here haha, my thermos have just started playing up.
Won’t switch to high speed when the car starts getting hot (like in slow traffic) fans stay on slow, which still stops it from over heating but it definitely heats up.
Hitting a/c doesn’t help, they cycle up and then shut off, presumably no gas in the a/c so it won’t let it run.

 

Tell me more, and I can help.

It's a simple system. Not much to go wrong at all.

Share this post


Link to post
Share on other sites

Ok to answer the transmission no it was never a Manuel converted from auto or video versa it’s always been a auto 2 J3 chip oh hell no wont use crap like that not even wouldn’t even use a shift kit thing for my car 3 can’t be ecu as it been changed twice an still does it an the reason why lm using a ef bcm is l scored a ef v8 fairmont donor wreck ages ago an wanted the dash for the digital climate  dash airbag an all that when l was building the original car when l was going thru chemo couple of years back. That was ridden off in front yard thanks to tree coming down so l transferred all from the wreck to this car which is a Ef xr6 there is a vid somewhere on here called Thor2.0 showing the original an then this build   I wanted something different to all other ef els out there  all l had to do was change couple of plugs around an get the bcm an ecu to talk other than that it’s still sorta el fairmont dash with just couples of plugs different in wires lol  

never had a issue with it being all from the 1st build until now it’s just started to happen an lve been slowly building this over the period of about a year?? I’ve had it running heaps of times no probs till the other day when it started that’s why l changed over the ecu an bcm to spare ones l had that came from good running cars an with. Fairmont climate control soon as u switch it onto aircon fans will come on as my mrs has a el fairmont an my daughter has a ef futura that has full rally cluster that’s original in it as it’s got the futura sticker on the housing an futura  factory fitted badges on the front fenders          . Just don’t know why it’s doing it now of all things as it was fine last week when I had it running in my garage till l put it under the car port 

Share this post


Link to post
Share on other sites

It’s all el harness all the way thru it except from the dash  will check it when it’s lite out   Wonder what it would be if they still run with the ecu unplugged as 2 ecu’s can’t be faulty at the same time like that 

Share this post


Link to post
Share on other sites

Well now l am really screwed as l unplugged the ecu turn key on an fans on low still, went over the harness an couldn’t find any breaks or loose connections anywhere.   Started it up hit aircon engine engine idle went up like usual even tho my aircon is pretty much deleted except for the aircon pump that’s been gutted so all that’s left is the housing an the pully as l couldn’t find a aircon delete one   Fans didn’t change speed at all so now lm pissed because l was meant to have it ready in couple of months to take to a meet in woodend next year.  

Share this post


Link to post
Share on other sites

Have you tried plugging in another set of fans to see if its not just that the ones yours using are faulty? Simple enough to check if you have access to another set, just put them close enough that they can be plugged in and see if they work properly, if nothing else it will confirm that the problem isn't with the fans your currently using.

Share this post


Link to post
Share on other sites

Yeah 4 sets of em including using the wife’s from her el fairmont. Even tried ef ones all same issue bloody on slow speed turn the aircon on engine picks up revs but not a single change in speed.  Almost ready to burn the bastard to the ground 

Share this post


Link to post
Share on other sites

All contacts are good as l hooked up a test light to the plug on fan end there is power on those the relays all new an when l pull em out an out em in again while key is either on or engine running they click and the fans power straight away an terminals are clean on the relays an on the sockets they plug into   ...l even looked at the fan relay box to see if there is a wire touching where it shouldn’t an none are.  

Share this post


Link to post
Share on other sites

If you unplugged the ECU and the fans still run,

start looking at either a stuck relay for the low speed circuit, or an external influence.

 

The ECU thermo-fan outputs, are ground side switched.

ie, the ECU connects the relay coil wires to earth/body/battery negative, to complete the circuit.

 

Therefore the external influence, means the low speed relay coil wire, has a short to ground (ie, battery negative),

somewhere between the relay box, and the ECU.

 

Should be fairly easy to locate, as both are on the same side of the engine bay.

 

Share this post


Link to post
Share on other sites

So it not a neg wire but the power wire which would be what color or is it the nether that’s shorting out somewhere between the ecu an relays?? If it a neg wire couldn’t l say just splice into the low fan neg and ground a new one to the body from that ?? Sorry lil out of it as lve just taken some pain killers as l just wrecked my shoulder 

Share this post


Link to post
Share on other sites

So would it be the blue with white trace wire that’s the relay coil negative on the relay an from the ecu?? Can’t see any wires from relay with any nicks exposing anything or from the ecu as all wires re fully covered   It’s doing my head in big time 

Share this post


Link to post
Share on other sites

Ok just did a trick.  I cut the blue wire with white trace at the ecu end turn key fans still went on .cut it at the relay hooked a wire to the relay end an to the ecu cut end on ecu Turned aircon on fans went on.  Turned aircon off Turned  heater on highest & lowest temp 16 with heater fan on low fans turned on turn. heater off fans off with motor running  so somewhere in the harness something has happened for fans to turn on at all times even with just ignition on but not running even if wire was cut at the ecu  so now that have hooked a new wire from the ecu plug out thru the window to the relay fans will now turn on with aircon on or with heater on hi or low temps turn heater off where screen says off on it no fans running do you think that was the problem wi th wire somewhere in the harness has possibly rubbed where l can’t see it ??  Sad part is l can’t just run the wire from the relay straight to the ecu on the left side as the wires for the relay run rite around past the front of the rad all the way into the drivers side then thru the damned dash to the ecu  that way sol gotta pull the dash out just to run it properly an everything 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×