Fordmods Logo

Issues with thermo fan... 

 

Page 1 of 2 [ 16 posts ] Go to page 1, 2  Next

 
 Post subject: Issues with thermo fan...
Posted: Sat Jul 21, 2012 6:02 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

After doing a check for diagnostic codes in my EL GLi wagon, I got code 778 (Passenger side thermo fan fault). I started the engine, with AC on max and the fan on the highest setting to start the fans up to see for myself, and sure enough, the driver's side was working a treat but absolutely nothing out of the other. Thought, ok, here we go, replace the fan. Simple.

Anyway, some of you may be familiar with EricTheCarGuy on YouTube, I personally find his videos really insightful. And he always raves about how much he loves his Power Probe tool. After seeing a cheaper version for $50 at Jaycar, I picked it up and got to work on making it useful.

I took the fans out of the car and unplugged the connector. There were four pins on the fan's end; two positive, two negative. After supplying voltage and ground, I saw that there isn't actually anything wrong with either of the fans, they were working perfect and the passenger side was spinning just like the driver's. Which leads me to guess that it's a connection issue.

Has anyone had anything similar happen, or any advice on where to look next?

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 6:15 pm 
Getting Side Ways
Offline
User avatar

Age: 32

Posts: 415

Joined: 13th Nov 2010

Ride: 95 EF GLI

Location: Melbourne
VIC, Australia

steedy wrote:
After doing a check for diagnostic codes in my EL GLi wagon, I got code 778 (Passenger side thermo fan fault). I started the engine, with AC on max and the fan on the highest setting to start the fans up to see for myself, and sure enough, the driver's side was working a treat but absolutely nothing out of the other. Thought, ok, here we go, replace the fan. Simple.

Anyway, some of you may be familiar with EricTheCarGuy on YouTube, I personally find his videos really insightful. And he always raves about how much he loves his Power Probe tool. After seeing a cheaper version for $50 at Jaycar, I picked it up and got to work on making it useful.

I took the fans out of the car and unplugged the connector. There were four pins on the fan's end; two positive, two negative. After supplying voltage and ground, I saw that there isn't actually anything wrong with either of the fans, they were working perfect and the passenger side was spinning just like the driver's. Which leads me to guess that it's a connection issue.

Has anyone had anything similar happen, or any advice on where to look next?


did it come on at all? the fans have 2 speeds, also check relays.

 

_________________

95 Ef Gli, mods : Tickford Head, Tickford ecu, Pacemaker 4499, Venom 100 cpi cat, Redback 2.5" catback, Wade 977b cam, ba xr6 intake and SS inductions, k & n filter & leather seats. 147.5kw @ wheels

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 6:20 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

it didn't move at all when the engine was running. the code says Fan motor not drawing current from battery when switched on by EEC during Self Test, and that seemed to be what was happening. the drivers one was working fine

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 7:43 pm 
Moderator
Offline

Posts: 14513

Joined: 7th Nov 2004

Ride: ford falcon au3 xr8

Location: a shit suburb in sydney
NSW, Australia

could be a relay playing up, the ecu only senses the load on the relay trigger.
so if the relay burns out, fails or there is a broken connection from the ecu to the relay it will come up with a fault code..
if the fan shorts or fan motor burns out it will blow the 60a fuse..
Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 8:08 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

well as i said, the fan motor is fine because i tested both the fans independently when i took them out of the car. by the sounds of it it may be a relay, but would that account for only one fan not working? if the relay is playing up wouldnt that mean that both fans either wouldn't work, or wouldn't go to the different speed?

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 8:22 pm 
Moderator
Offline

Posts: 14513

Joined: 7th Nov 2004

Ride: ford falcon au3 xr8

Location: a shit suburb in sydney
NSW, Australia

you have "from memory" 3 relays in el 1 for left fan 1 for right fan and one for a/c fan trigger..

and ef has 4 relays 1 for left fan, 1 for right fan, 1 to trigger both fans on low speed and 1 for a/c fan trigger..
Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 8:29 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

ah well that might be it then! i'll be having a look at that tomorrow, thanks!

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sat Jul 21, 2012 10:28 pm 
Getting Side Ways
Offline
User avatar

Age: 32

Posts: 415

Joined: 13th Nov 2010

Ride: 95 EF GLI

Location: Melbourne
VIC, Australia

TROYMAN wrote:
you have "from memory" 3 relays in el 1 for left fan 1 for right fan and one for a/c fan trigger..

and ef has 4 relays 1 for left fan, 1 for right fan, 1 to trigger both fans on low speed and 1 for a/c fan trigger..


i shouldve of elaborated a bit more, basically exactly what troy said, the fans have 2 speeds and seperate relays

 

_________________

95 Ef Gli, mods : Tickford Head, Tickford ecu, Pacemaker 4499, Venom 100 cpi cat, Redback 2.5" catback, Wade 977b cam, ba xr6 intake and SS inductions, k & n filter & leather seats. 147.5kw @ wheels

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 12:25 am 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

Do you remember which ones which? I had a look at the wiring diagram but couldn't make sense of which relays ended up to which fan

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 12:28 am 
Getting Side Ways
Offline
User avatar

Age: 32

Posts: 415

Joined: 13th Nov 2010

Ride: 95 EF GLI

Location: Melbourne
VIC, Australia

steedy wrote:
Do you remember which ones which? I had a look at the wiring diagram but couldn't make sense of which relays ended up to which fan


nah i said f**k it and sent it to an auto elec

 

_________________

95 Ef Gli, mods : Tickford Head, Tickford ecu, Pacemaker 4499, Venom 100 cpi cat, Redback 2.5" catback, Wade 977b cam, ba xr6 intake and SS inductions, k & n filter & leather seats. 147.5kw @ wheels

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 10:01 am 
Getting Side Ways
Offline

Posts: 496

Joined: 14th Sep 2011

Ride: BF II Gas Ute

Location: Canberra
ACT, Australia

Hi,

There are 3 relays as mentioned, the fans can run separately on full power which is fast. To run on slow they run in series, the power goes through both together which means they both run slow. ( half voltage in each ) Behind the Pass side headlight there is the relay bank under a cover. There is 3 relays, 2 are a normal type and the same. The other has change over contacts to let it run both fans in series. They will be a different colour and the change over will have an extra pin. Both will be available at Jaycar, Mark them with Texta and change them over one at a time. Do the test to run them fast and you should get it sorted. There is a Tech Doc if you need more info.

Regards 96ELGli

 

_________________

Regards 96ELGli

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 3:51 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

96ELGli wrote:
Hi,

There are 3 relays as mentioned, the fans can run separately on full power which is fast. To run on slow they run in series, the power goes through both together which means they both run slow. ( half voltage in each ) Behind the Pass side headlight there is the relay bank under a cover. There is 3 relays, 2 are a normal type and the same. The other has change over contacts to let it run both fans in series. They will be a different colour and the change over will have an extra pin. Both will be available at Jaycar, Mark them with Texta and change them over one at a time. Do the test to run them fast and you should get it sorted. There is a Tech Doc if you need more info.

Regards 96ELGli


Very helpful, I may have found the problem but I'm not sure. According to the doco, relay 1 (white) supplies power to the left fan, relay 2 (green) supplies power to the right and ground to the left, and relay 3 (white) also gives ground to the left. I took out relays 1 and 3 one at a time and nothing happened, which was expected because the left fan wasn't working anyway. I switched them over and nothing happened. When I took out relay 2, the right fan stopped working, as expected. I believe it may be relay 2 that is causing the issue but am still not sure. For the left hand fan, power goes through relay 1 and ground through relay 2, but ground also goes through relay 3. Would it need both relays to be working properly?

This will be the relay that you said lets both the fans run in series, so maybe it is just that bit of the relay that must be stuffed? Seeing as its giving power to the right fan just fine.

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 7:59 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

On a possibly related note... I just got home from a 20 minute drive. It's a cold Melbourne winter night, I get home, switch the engine off, and I hear a gurgling sound. I pop the bonnet, a waft of warm air hits me in the face and I find the source of the noise: the coolant in the reservoir is boiling. I definitely would not expect that from a short drive in little traffic on a cold night. I recently took the car in to do a RWC, and our mechanic flushed and refilled the coolant. The level has been fine, so I don't think its a matter of not having enough in there. It has the red stuff in there, same as it did before.

The weird thing is that the temperature guage says that it is fine, over the week that I've had my P's, including sitting in peak hour traffic on the way to school, I've never seen it creep past the R in NORMAL, and same tonight. Is it lying to me?

Now I don't believe one fan not working could cause this. It probably wouldn't have helped, but I might be looking at something else here as well... Ill keep an eye on it during the week.

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 9:56 pm 
Getting Side Ways
Offline

Posts: 496

Joined: 14th Sep 2011

Ride: BF II Gas Ute

Location: Canberra
ACT, Australia

Hi,

With any luck there was some air in the system that has now come out. When you work on the cooling system, run the engine for 5 minutes at 2000 rpm with the heater on full. This should purge the air from it. You may even have a faulty radiator cap. For a few dollers I would swap it and keep the old one as a spare.

I am not being patronizing here, but as you are a young guy you may not know about heat-soak. After you turn the engine off, the heat is no longer being pumped away by the cooling system, so the coolant temp will rise. ( heat from the block ) If the cap isnt holding pressure it may boil. If you watch the temp gauge, when you stop and jump in again after a few minutes the temp will go higher than it was.

On an older Carb engine, in winter the Carb can ice up. The engines stalls, you get out and start looking at things then try again and it starts. Heat soak again, that is why they used stove pipes to get hot air from near the exhaust to stop this. ( a bit of history in this EFI world ! )

Bottom line it may be a simple cap replacement, unrelated to the other issue. If you havnt boiled it or run without coolant you shouldnt have caused anything with 1 fan out.

Regards 96ELGli

 

_________________

Regards 96ELGli

Top
 Profile  
 
 
 Post subject: Re: Issues with thermo fan...
Posted: Sun Jul 22, 2012 10:22 pm 
Smokin em up
Offline
User avatar

Posts: 218

Joined: 28th Apr 2012

Ride: EL Wagon, DF LTD

Location: Vermont South
VIC, Australia

96ELGli wrote:
Hi,

With any luck there was some air in the system that has now come out. When you work on the cooling system, run the engine for 5 minutes at 2000 rpm with the heater on full. This should purge the air from it. You may even have a faulty radiator cap. For a few dollers I would swap it and keep the old one as a spare.

I am not being patronizing here, but as you are a young guy you may not know about heat-soak. After you turn the engine off, the heat is no longer being pumped away by the cooling system, so the coolant temp will rise. ( heat from the block ) If the cap isnt holding pressure it may boil. If you watch the temp gauge, when you stop and jump in again after a few minutes the temp will go higher than it was.

On an older Carb engine, in winter the Carb can ice up. The engines stalls, you get out and start looking at things then try again and it starts. Heat soak again, that is why they used stove pipes to get hot air from near the exhaust to stop this. ( a bit of history in this EFI world ! )

Bottom line it may be a simple cap replacement, unrelated to the other issue. If you havnt boiled it or run without coolant you shouldnt have caused anything with 1 fan out.

Regards 96ELGli


Yeah the radiator cap was my guess. I left it for a while, then took it round the block and then sat on about 2000rpm for long enough to get the temp gauge up to where it was when i was driving before. I then put the cluster in diagnostic mode and got the coolant temp as around 105, which shouldn't be enough to make it boil, especially if it is under pressure. So that's what I'm thinking. And for poo change, I may as well give it a shot.

Haha no offence taken mate. Because I'm doing chemistry in year 12 it does give me some idea on the theory behind things, but when it comes to cars I only know what I've taught myself, and read on here from intelligent folk such as yourself. I will keep that heat soak in mind while I watch it for the next few days.

 

_________________

The gene pool could do with a little bit of chlorine...

Top
 Profile  
 
Display posts from previous:
Sort by  
 Page 1 of 2  [ 16 posts ]  Go to page 1, 2  Next

Who is online

Users browsing this forum: Google [Bot] and 31 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

 

 

It is currently Mon Dec 11, 2017 9:12 pm All times are UTC + 11 hours

 

 

(c)2014 Total Web Solutions Australia - Australian Web Hosting and Domain Names