jcasey007
Well-Known Member
- Joined
- March 17, 2009
- Messages
- 521
- Reaction score
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- City, State
- Stratford Upon Avon, Warwickshire
- Year, Model & Trim Level
- Jeep Commander 5.7L HEMI
You know the symptoms, the aircon fan will only work on very slow or full speed.
The fix is to replace the resistor unit located under the aircon fan unit.
Problem is I've done this 3 times this year, replacing with good second hand units as no new ones are available in the UK.
I've kept all the ones I've removed and the thought of skinning my knuckles again tomorrow changing it, got me thinking.
"which part of this simple assembly is failing"? so I started looking at the replacement ones (thanks Chris) and the three 'broken ones' I've kept.
When you actually look closly at these assemblies all they consist of is three coils of resistance wire (very low resistance) and a fuse link.
None of them had burnt out coils or a blown fuse and then I found the common problem.
All of them had corrosion on the wiring socket terminals, you can't see very well because of the plastic housing. So I set about refurbising a couple.
By the way you can tell if the resistance coils are shot, use a digital ohm meter, across the three different coils and you should get 2.2 ohms, 2.9 ohms and 3.1 ohms.
So the refurb.
Step one - Carefully drill out the two rivets that hold the plastic socket to the back-plate this is what you see. Note the corrosion on all the terminals. The one in the middle is always the worst.
Step two - Use a small fine grinding wheel (no bigger than 5mm diametre) from a dremmel , carfully grind and polish each side of each connection until you see bright metal as in Picture two.
Step three - Pop rivet the plastic cover back on to the base plate, total time - 10 mins a unit, good as new if fact so good I did all of my broken ones.
A few years ago I built a home nickle electric plating set for replating these typs of components, I wish I still had it.
cheers
Jim
The fix is to replace the resistor unit located under the aircon fan unit.
Problem is I've done this 3 times this year, replacing with good second hand units as no new ones are available in the UK.
I've kept all the ones I've removed and the thought of skinning my knuckles again tomorrow changing it, got me thinking.
"which part of this simple assembly is failing"? so I started looking at the replacement ones (thanks Chris) and the three 'broken ones' I've kept.
When you actually look closly at these assemblies all they consist of is three coils of resistance wire (very low resistance) and a fuse link.
None of them had burnt out coils or a blown fuse and then I found the common problem.
All of them had corrosion on the wiring socket terminals, you can't see very well because of the plastic housing. So I set about refurbising a couple.
By the way you can tell if the resistance coils are shot, use a digital ohm meter, across the three different coils and you should get 2.2 ohms, 2.9 ohms and 3.1 ohms.
So the refurb.
Step one - Carefully drill out the two rivets that hold the plastic socket to the back-plate this is what you see. Note the corrosion on all the terminals. The one in the middle is always the worst.
Step two - Use a small fine grinding wheel (no bigger than 5mm diametre) from a dremmel , carfully grind and polish each side of each connection until you see bright metal as in Picture two.
Step three - Pop rivet the plastic cover back on to the base plate, total time - 10 mins a unit, good as new if fact so good I did all of my broken ones.
A few years ago I built a home nickle electric plating set for replating these typs of components, I wish I still had it.
cheers
Jim
