i have a 96 e320. i wanted to know if someone could answer my question. the temp on my car gets a little high toward the 120 when im driving. im goin to change the thermostat but i also noticed that my auxillary fans are not coming on. do they suppose to come on when the ac is on or do they come on at a certain temp?
All of the above. I don't recall the exact criteria, but I do know that they should be on high when the engine coolant hits 120.
First check to make sure that you can easily turn the fan motor by hand, where it sticks out through the plastic guard (with the hood open). It should rotate quite easily with no drag at any spots, and the right side should turn with the left.
Second, ensure that the fuse is good. It's in the underhood box.
If all the above looks good, next step:
With the key in position 2 (engine running or not), hold down both AUTO buttons on your climate-control pushbutton unit for more than ten seconds. It takes about twelve seconds on my car. That puts full current to the auxiliary fan control module. If you hear the fan, the pushbutton unit is not getting the criteria to start. If you can't, hold down the REST button for more than five seconds until the display changes, and scroll to 20 on the left, using the AUTO keys. The right side should read 10 (if not, use both AUTO keys again; you didn't hold them long enough the first time). Once you get a reading of 10, go watch the fan. If it pulses (trying to start) about once every eight seconds, either the fan motor or the control module (or both) is bad. This control module is not the pushbutton unit; it's probably in the underhood fusebox.
hmm i didnt know that.... My fans are on ALL the time... and stay on like a minute after i shut off the car... my temp usualy stays at the middle range... doesnt get high or anything. now i know theres something wrong there... i dont know what, but i think its cool how my fan shuts off like a minute after the car does.... people always think my car is still running, up untill i jingle my keys in the air.
ok i did the test. i hit the auto buttons for 10 secs and the fans didnt come on. so i hit the rest for 5 secs and set the left to 20 and the right display read 10. i went to the front and the fans still werent on. i checked the fuses but didnt really know the location of the fuse. would anyone happen to know where the fuse in the engine department is located or a fuse number. i checked them all and they didnt seem to be blown
I Believe its a Relay.... If not that... theres a little black box under your brake booster that control the fans... maybe theres something wrong with that.
The fan spins freely? You see no pulsing on about eight second intervals? The next step is to put the unit in fan test mode again and check for voltage at the connector, with the fan disconnected. If the control module is working properly, you should see no voltage most of the time, except a number of very quick pulses, about once every six seconds. I think the fan fuse is #19, if you have one. My E300 does not.
I hate to inform you of this, but there isn't exactly a relay, and there is one of three possible systems in your car.
Originally, N22 (climate-control pushbutton-unit) fed N65 (pulse control module). N22 is in your dash, N65 is inside the under-hood fusebox. You have to remove six screws (two are under the fuse cover) to see N65. Mine has this system, and the dealer no longer supplies the proper N65 for my car; I would have to update to the latest setup, at a cost of over $800 (N10-1 is pricy). Your case is probably different, since you have a gasser.
On slightly later models, N22 fed N65/1 (auxiliary fan control module) which is located behind the left headlight.
Later still, N22 feeds N10-1 (combination control module) which sits in the module box near the heater fresh-air intake under the hood. N10-1 feeds N76 (auxiliary fan control module again) and I have no idea where that sits.
i hate to sound crazy but i am so lost on what i need to do now.i think i may have the n65. when i take the cover to my the fuse box under the hood there is another cover with 6 screws that i took off once but didnt have a clue what i was looking at. so if i do have the n65 what do i need to do from here. ( i will also check fuse 19 and see if that is the fan fuse)
That's mostly background information. N65 sits behind the fuses, and forms part of the wall of the fusebox, on the side toward the fender. It has a number of wire connectors on it, and runs more than the auxiliary fan.
Check the voltage at the fan connector with the system in test mode (i.e., hold both AUTO buttons for >10 seconds) to see if you get pulses of voltage about every six seconds.
Linear Mode
