Cooling (radiator) fan not working, '05 ZT 190

[White horse]

Thanks all for the info, I'm hoping the new brushes will arrive tomorrow and that will sort out the fan problem. Then it will be on to the next problem!

[White horse]

New brushes arrived today, fitted and fan back on the car, tried the demist test and all is well! Relieved and happy with that.

Incidentally, from what I have read on the forum I thought I would need to remove the fan housing from the car to do the job, either by degassing the air con or cutting the housing away as necessary. No need, with the housing released from one end and the bottom of the radiator there was enough room to do the job. Might have been a different story if the screws holding the fan didn't undo.

Right, next problem..........

Thanks for all the advice,

John

[SD1too]

Originally Posted by White horse

New brushes arrived today, fitted and fan back on the car, tried the demist test and all is well!

Well done John!

Why do some people make such a fuss about fitting new brushes?

Simon

[Arctic]

Originally Posted by White horse

New brushes arrived today, fitted and fan back on the car, tried the demist test and all is well! Relieved and happy with that.

Right, next problem..........

Thanks for all the advice,

John

Hi John.
Excellent I think you may have been lucky with the three torx screws to release the fan motor and blade from the cowling anyways job done and you should have a good few years service out of the fan once again did one my self a week or so ago just need to add a gold resistor to it, good luck with the rest of your projects Arctic

[White horse]

The hardest part of the job was opening up the motor, bending the tabs. likewise bending the tabs to close the motor up.

Torx screws, something I found out the hard way is that while the correct size "bit" fits (obviously!) the next size smaller does, sort of. Very neatly destroys the socket so its out with the drill.

[SD1too]

Originally Posted by White horse

The hardest part of the job was opening up the motor, bending the tabs. likewise bending the tabs to close the motor up.

Agreed. I'd rather do that than bash away at suspension ball joints and bushes though!

Simon

[Arctic]

John & Simon.
Trick is and you learn quick if you do as many as I have over the last few years, squash the tags together first,
1

Then with the mole grips squeeze the tag and lid together and it pops them through
2

3

4

John managed it, so all is good I am sure a few other members could go down this road as some of these motors are in good condition, all they need is cleaning up
5

6

7

Opened brushes checked & changed, rewired ready for gold resistor and go to give good service
8

I have had mine on now for 4.5 yrs and still going strong

[SD1too]

Originally Posted by Arctic

Trick is ... squash the tags together first ... Then with the mole grips squeeze the tag and lid together and it pops them through.

That's a great tip Steve, thanks. I think you've mentioned this before.

I have had mine on now for 4.5 yrs and still going strong

7 years for me Steve!

Simon

[MDMH757]

Evening all,

I have noticed my radiator fan not working on Demist test, I think it is the 3 speed as its got two tabs with screwholes (unused) but no resistor at the 2 o' clock position.

my car is a 2003 (52plate cdt), please can someone point me in the direction of a "how to" outline the order to find out where problem lies... I believe from reading it could be the brushes? is there a "how to" to fit them? & where would the best place to buy some? Finally, am I okay to drive as long as I dont get stuck in traffic queues?

Cheers

Maurice

[Jules]

Originally Posted by MDMH757

Evening all,

I have noticed my radiator fan not working on Demist test, I think it is the 3 speed as its got two tabs with screwholes (unused) but no resistor at the 2 o' clock position.

my car is a 2003 (52plate cdt), please can someone point me in the direction of a "how to" outline the order to find out where problem lies... I believe from reading it could be the brushes? is there a "how to" to fit them? & where would the best place to buy some? Finally, am I okay to drive as long as I dont get stuck in traffic queues?

Cheers

Maurice

Hi Maurice

3 speeders fail from 60k miles almost like clockwork !

Rebrushing often futile as commutator will have a deep groove in it.

Old style 3 speed with no resistor.
(life expectancy of 60 -80k miles)

Later types with resistor fitted can usually be repaired

Check through front grill with torch or see this this link for info

2 Fan types
Note a resistor kit will not fix the old 3 speed type with no resistor

http://www.the75andztclub.co.uk/foru...ad.php?t=68336


DIY test here
http://www.the75andztclub.co.uk/foru...ad.php?t=35567

I have all eventualities in stock.

Treat yourself to an upgraded kit
Uprated longlife Revotec cooling fan kit
http://www.the75andztclub.co.uk/foru...d.php?t=189409


Finally some DIY diagnostics:

Fan Control box DIY test check.

First of all you need to check your fan control box is functioning correctly.

Select demist (ignition ON engine OFF for diesels)

Get someone to listen at the front grill while you press ECON button every couple of seconds.
The low speed fan relay should be heard clicking.

The same can be done with the high speed relay by carrying out my Trinary switch test......

http://www.the75andztclub.co.uk/foru...ad.php?t=35567

The above will prove whether the PWM PCB in the control box (diesels) is responding from ECU commands.

General fan tests:

For no Low or High speed check the following:

Check 80amp fuse no 4 in engine compartment.(very rare to fail)

Check the large and small relays in the fan control box (carefully lever 10 clips on the lid to inspect)

Wire breaks have been known between the 2 multi-plugs (behind LH wheel arch liner) and the control box.

Check fan earth CO551 (ring terminal between battery box and inner wing secured by 8mm bolt or measure with meter whether the thick black wires from the control box are in fact earthed)

Check continuity of all wires coming into and leaving the fan control box. Wire breaks and joint breaks can happen in the thick or thin cables. Look for tell tale signs of green copper oxide along the cables to the multi-plugs. Water ingress may have corroded the copper strands.

If all in order there may be a break in signal lines from ECU to fan control box or on extremely rare occasions the ECU itself could be faulty.

Extra notes for Revotec installs not working years after fitting:

One general mistake here is not waterproofing the connectors with grease of self amalgamating tape resulting in corrosion and hence bad connections at the white plug.


Let us know what you need