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UK 1995 W124 300d Om606 Estate
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Discussion Starter #1
Hi, my 1995 E300d AC pusher fans are not coming on. They were working not long ago when the ac was turned on but now don't run at all. I have been avoiding using the ac while the car is stationary but want to sort it out. I have checked fuse no 7 in the box and have checked what I thing is the main fuse next to what seems to be the ac fan relay but can find no problem.

Am I missing something? The fans are free and I'm sure the motors work, they spin freely and were running recently. Can anybody help? :confused: thanks
 

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04 odyssey (265k) 1995 E320 wagon (295k)
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2,988 Posts
You mean the auxilliary electric fans in front of the A/C Condenser?
They are added fan power to help cool the engine. If your engine temps are not getting over 105F (that right guys?) you'll never hear them come on.
Feel free to use A/C, just watch engine temps.

If cabin fan power is low, might be squirrel cage fan (common wear item on these cars)
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #3
I thought they were supposed to come on when the ac was turned on regardless of the engine temp?
 

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384 Posts
There's a switch based on AC pressure that turns them on. Short the switch on and see if the fans work, that will tell you if you have a bad switch. There should be another switch for temperature, that could tell you whether it's the low speed resistor (ac switches low speed on) that's bad.

If the fans are seized up, that's easy to determine by hand.
 

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W124 Moderator
86 190E 2.3L 16V, 2 95 320TE's, 02 S500
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12,756 Posts
The aux fans have two speeds. Low speed is triggered when the A/C is on. If the fans don't engage, chances are your system is low on freon. The fans kick to high speed when the engine temps reach approx 105 degrees.

Jayare
 

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UK 1995 W124 300d Om606 Estate
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13 Posts
Discussion Starter #6
The fans turn freely, the AC compressor engages so I presume the fans should run. I'm still trying to find the resistor that runs the low speed stage. The relay for my AC fans is not in the fuesbox but on the other side on it's own with it's fuse.
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #7
OK, I have just started the car, the ambient temp is about 20c. I left it running for a while until it got warm ans then turned the AC on. Shortly after this the AC pusher fans came on fast I think and ran for about 40 secs. They then turned off, coming back on again in 30 secs or so as it warmed up again. It justbseemsbthat the low speed function is not working, I suspect the resister but can't find it. Could it be inside one of the fans?
 

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1995 E320 sedan, 1991 Porsche 964, 2004 Porsche 986
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450 Posts
The auxiliary fan resistor is behind and below the left-side headlight inside the engine bay.
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #9
I don't think it is, I can't find it there. My car is a RHD UK car, could anybody give me an idea of what I'm looking for, any pics? thanks
 

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04 odyssey (265k) 1995 E320 wagon (295k)
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Be prepared for the requests to fill out your profile...

Moth..you out there? Can you help this bloke? (I rarely can use "bloke"...so I took my opportunity)
 

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W124 E420 : W220 S500 : W222 S550
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this can be a tricky character. sometimes it looks just fine but there will be a short in the connectors, wiring, and the resistor itself, that are sometimes not visible to the eye. Other times its a real obvous blowout.

Also depending on your profile:wink_2:....... it could be the low speed relay or its fuse..... among other things....


here and this is the first request to fill out your profile. It does help... really
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #13
Where will I find this thing? I will fill out the profile, a bit new to the whole forum thing. thanks:)
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #14
Ok, I have looked under the headlights, under the abs unit, I have looked everywhere. No luck, the wiring for the fans just goes through to the scuttle panel, to the relay and fuse than across to the other side. I have looked by the fuse box and in the relay box. :(
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #16
I can't understand that, my car is a diesel (300d) so I don't think it's applicable. I"m still trying to find this resister! :(
 

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Premium Member
1993 400E, 2019 Sprinter 2500, 1991 420SEL, 1977 280SE
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308 Posts
If the fans come on at all, it is not likely that you have a problem with fuses or relays. More likely that the freon level is low, A/C pressure sensor is bad, or wiring is shorting. 1992 to 1996 had biodegradeable wiring and they are notorious for causing issues.
 

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UK 1995 W124 300d Om606 Estate
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Discussion Starter #18
The fans have only ever run at high speed so I think this could be the problem, if only I could find it. I'm going to do some motorway driving today. Is it OK to run the AC when the cars moving?
 

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Premium Member
1993 400E, 2019 Sprinter 2500, 1991 420SEL, 1977 280SE
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308 Posts
The fans have only ever run at high speed so I think this could be the problem, if only I could find it. I'm going to do some motorway driving today. Is it OK to run the AC when the cars moving?
I would say yes, with this caveat: watch temperature closely and be sure it does not 'redline' and if the air is not cold from the vents with A/C on you know the R134 pressure is low for sure.
 
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