Engine FAN Relay 1 Melts, Help needed.....(Post with Pictures)

[frontier]

Hi Guys,

im from kuwait, i have Commodore VY SS 2004 8Cyl ( called chevrolet Lumina SS). as mentioned in title, engine fan relay 1 gets too hot when fans run at engine temperature and often one leg of relay melts and stop working which has also melted the female connector on the relay panel.this makes engine temp to rise.i have to often change that relay to avoid temperature.
i would like to mention that i changed thermostat, temp sensor and all the hose pipes. all fuse checked and there is no problem other than this. i suspected fan motors but they seems working fiine. i have added pictures.i took it to local dealers but they were unable the tell what exactly makes that.
please if any one has experienced such problem or know what and where the problem exactly is.....

[GenReaper]

Could be either a bad earth in the system.

My bet would be need a higher amperage relay fitted.

If the fans motors have a short or are on their way out they will also draw too many amps.

[redvsberlina]

Bigger relay is asking for troubles it feels like a earth leak thus the higher amps going through the relay id trace that wire back to the fan my bet is that it has ha the protective plastic compromised somewhere were it can loop before the fan

[delcowizzid]

being that its only one pin its most likely a loose or bad connection on that one pin of the relay which makes lots of heat when they are struggling for contact.fit a new crimp in the slot

[VTPREDATOR]

[QUOTE=GenReaper;1558275]Could be either a bad earth in the system.

My bet would be need a higher amperage relay fitted.
QUOTE]

great idea! if you want to burn the car to the ground.

[frontier]

iv found the connector and the wire beneath that base also with burnt insulation because of heat. i took out that pin, taped the wire and installed new pin but its still reaching extreme heat when fans work. i think one of motor is short and running high amp OR bad earth,


so if we suspect either can any one help me how to check and find the faulty motor and if bad earth is a case then how to fix that.does that means i have to pull extra -ve cable from battery to the body ??..

[whitey66]

If it's a bad earth you will get less current flow and less heat.
You've either got:
A bad connection or connections (check with a voltage drop test across the circuit while the fan is operating).
A partial short to earth on the power wire,causing excessive current flow.
Faulty blower motor that is consuming too much power.
Or a faulty relay.
Don't put a higher amperage relay in it,that will achieve nothing at all.
You can measure the current draw of the circuit with an ammeter and compare it to a car the same that doesn't have the problem.

[paavt]

Holden (GM) did create a fix for this by way of a small fan relay patch harness which was created to overcome this overheating issue over your way.
I will do some checking in our system at work tomorrow and see if I can find the part number and some details for you so you can chase up the fix.

[GenReaper]

[QUOTE=VTPREDATOR;1558634]

Could be either a bad earth in the system.

My bet would be need a higher amperage relay fitted.
QUOTE]

great idea! if you want to burn the car to the ground.

Not at all i spose you do know they run a fuse in most cars, lol

Seems like paavt is on the money so all is good.

[whitey66]

Removed post,wrong info

[frontier]

well here in kuwait, most people blame and dislike commodore for its electric and heating problems. im in hot country reaching 45 to 50c most of time and have little winter, i think that makes such problems worse.

today ill try to check the problem with amp meter, the patch relay harness may b an option so please let me know the part number and details.

[colgf]

Hey Buddy - Your Relay base receptacle has 5 terminals , how come you're using a 4 lug relay???? I think you need to buy a correct 5 lug relay & try that . Maybe theres an internal difference between a 5 pin & a 4 pin relay, thats allowing a short in the relay. You still need to replace that burnt terminal . See how you go .

[redvsberlina]

we have a winner !!!

[frontier]

now thats a catch, iv never noticed that because since i bought this car,it came with four legs relay and i always change with the same one. ill try with five legs and see if this is the reason...thanks buddy...

[D3CID3R]

might give you some answers for the 5th pin

[frontier]

Thanksssssss...since i posted last reply, i was searching for relay and circuit details.....do you have complete fan circuit diagram for vy ???



if the melting pin is 86 then its just a trigger pin and has nothing to do with fifth pin 87a or faulty fan motor... !!!!!! any how im going to replace with five pin relay and see..might helps.

[colgf]

I just looked up my WH Statesman Wiring manual (same fan system) & this 5 lug relay is hooked up in the system thru the 4 lug relay next to it. Its quite complicated but I think the end result is that when you have Aircond on you get both Fans Running all the time. When the Engine gets hot enough you get only one fan on/off cuts in & out. When the engine gets too hot you get both Fans on, until it cools down. There's wires that run back to the Body Control module too. I cant get a pic of the wiring diagram to post. But I remember one thing, if you put a 4 lug relay into the 5 lug receptacle the engine cycling fan does not work at all , so in your case the engine will be running too hot all the time thus triggering both fans to run all the time . Thus that constant heavy current thru the relay may be burning out that terminal. Its a weird circuit to explain.

[frontier]

Great.......!!!!!!!!

do any one have parts manual software like the one dealer use to have to know exact part numbers and details.????

[paavt]

Great.......!!!!!!!!

do any one have parts manual software like the one dealer use to have to know exact part numbers and details.????

Checked our system and confirmed with engineers that the fan patch was not for your issue.. You are on the money with the incorrect relay being used as you must ensure you have the genuine 5 pin relay from GM. Not 100% sure why but I fitted a non genuine 5 pin in our own car earlier this year and the fans just remained on all the time. Then purchased a genuine relay from GM for the Fan and all has been fine since then.
Not sure on the part number of the relay but should be a white coloured part from memory.
As all the other guys have mentioned you must also ensure all the wires and terminals that have been burnt are fixed as well.
Hope this helps

[D3CID3R]

Checked our system and confirmed with engineers that the fan patch was not for your issue.. You are on the money with the incorrect relay being used as you must ensure you have the genuine 5 pin relay from GM. Not 100% sure why but I fitted a non genuine 5 pin in our own car earlier this year and the fans just remained on all the time. Then purchased a genuine relay from GM for the Fan and all has been fine since then.
Not sure on the part number of the relay but should be a white coloured part from memory.
As all the other guys have mentioned you must also ensure all the wires and terminals that have been burnt are fixed as well.
Hope this helps

So you installed a normally open relay instead of a normally closed relay.

[paavt]

So you installed a normally open relay instead of a normally closed relay.

Most lilkely but the relay we purchased definately was meant to be a direct replacment but as I say it did not work. Hence why it was best to get the correct OE part in this case.

Cheers

[frontier]

yes guys ,i have replaced it with 5 pin white color relay and since its seems working fine.. i have also replaced the female pin and wire also...thanks guys for helping.i think holden must had changed the socket type and pins layout for this specific relay so no one replace it with 4 pin by mistake.....im greatfull to colgf for help and to all other members

GM dealer couldnt find that problem when i visited.do they hire dumb technicians and untrained..

[colgf]

Thanks for the praise but thats what this website is all about. I have learned heaps from other posts & everyone benefits. I wonder how many other commodes are out there with the wrong relay fitted??? Classic case of GMH not making a system idiot proof. Best of luck in the "Sand Pit" over there.......