how do i fix my radiator fan?
Asked by supermegatronitron Mar 27, 2013 at 03:33 PM about the 2000 Jeep Grand Cherokee Laredo 4WD
Question type: Maintenance & Repair
i recently bought a 2000 jeep grand
cherokee 4WD laredo an i was told it
was the fan relay i replaced the fan
relay and the fan still doesnt come on
39 Answers
jump power and ground to the fan its self and see if it runs. then you will know if the fan is bad or if you need to be looking somwhere else.
When do you think it should turn on? Is the engine overheating?
supermegatronitron answered 11 years ago
i was told it usually turns on at 217 or so but i try not to let it get past 220
migration_judge_roy answered 11 years ago
you want us to find a thermostatic switch for you?
supermegatronitron answered 11 years ago
i would just like to know what could be causing this problem like kbro said it could be the fan
It could be that your engine isn't getting hot enough.
supermegatronitron answered 11 years ago
@tenspeed when is it usually supposed to turn on?
supermegatronitron answered 11 years ago
@judge_roy_beans i think it is im not quite sure though
migration_judge_roy answered 11 years ago
what is there to think through? switch and fan...guess I missed any meetings of the board that planned for more than this~
supermegatronitron answered 11 years ago
well this is my first vehicle so i dont know much if you're not here to help me then idk why you're here
if its gettin to 220 degrees it should come on by then.
migration_judge_roy answered 11 years ago
well start testing the suspected components, you've already replaced the relay, the fan motor and thermoswitch are the only other pieces to test~ no? You could test the switch to see if it is open or has continuity, test the fan to see if it comes on? no punctuation? idk, not I don't know? talk about bein' considerate of those trying to help you...spelling and grammar would be a start~ hate to report you as abusive because you only have a reputation of zero, you might think about being nice to those who are givin' you props~.
Here's where the temperature sensor is ----- http://www.youtube.com/watch?v=n4ryELEThGw
Possible fan relay location: http://www.youtube.com/watch?v=E5K1D1iEQO8
supermegatronitron answered 11 years ago
i tend to help others in need thats just who i am others just exploit those in need
supermegatronitron answered 11 years ago
no need to wonder i just joined this site
migration_judge_roy answered 11 years ago
Best of lucksupermgatronitron to you! hope we didn't get off on the wrong foot, really do want to help people now....no other hidden agenda, they are paying me nothing, just would like to impart what little I know from my four years as a professional mechanic "all makes and models"~sure, yeah~ you get ten from me, just because I can~
supermegatronitron answered 11 years ago
i do not feel we got off on the wrong foot, i was just simply speakin my mind. i felt a little disrespected yes but other than that no hard feelings
migration_judge_roy answered 11 years ago
I did not ask to be No.6 guru, in fact preferred having nothing, that way was not expected to know everything about ever car, as it stands DO have to research to get the answer, many times the pool of information is tainted, we just do the best we can with the information we can scrape up. no one person knows everything, I've had a couple of cases where I said 'hold on while I check someone who knows' a lot of time am cast out on my own with nothing to turn to 'cept my better judgement, the jetronic fuel system is one such case---even hearing detailed explanations are befuddled by these expanations has like 26 parts whereas today's systems are just a pressurized fuel rail and controlled pulses to the injectors- much simpler and elegant-
supermegatronitron answered 11 years ago
well im glad to know i have some people who know what they are talking about giving me suggestions. i appreciate all the help, im just ready to get my jeep on the road
migration_judge_roy answered 11 years ago
so turns out we're going to be replacing a few parts, the thermo-switch and ? relay done. fan motor ?
Hey there Mark. I don't know if you got your issue resolved about your Jeep and the Radiator issue. But here goes. I really loved it better when the only computer on a car was the one in the back seat in the latptop case, however, I have a Grand Cherokee and IT in fact decided to give me a fit. The fan didn't turn and as long as I was moving down the road, moving air through the front I was good to go. However, stop at a traffic light or 3 and then the temp would climb and the Fan would never come on. Now then, an old trick to help with cooling it. Summer time makes this VERY uncomfortable however, turn off the AC at the button and then turn on HEAT all the way hot AND Max Fan Speed. That will give you a "MINI cooling Fan" by way of the heater core fan assembly. Then moving again down the road the temp on the gauge then returns to practically normal. IF THAT IS HAPPENING then Radiator is fine as far as it goes. You are cycling water through the system and the movement of the air through the radiator when moving is cooling, along with the heater blower helping out. Now then Just what is failing. Basically there are 3 things. Fuse, the Relay and the Fan motor itself. In the fuse box under the hood there are a couple of the 40amp fuses and so I simply switched on for another and no change, the electric fan doesn't turn. So that leaves the Relay and the Fan Motor itself. Unless you have a nice multimeter and know how to use, the easy thing is to simply just undo the electrical connector to the fan motor. It is there the 2 wires running from the fan motor. Unplug it, then take some wire and run wires from the connector to the battery. BE CAREFUL NOT TO SHORT OUT THE WIRES !!!!!!!! It isn't a footrace to check the motor and could save you fuses and/or other issues, up to and inclucing blowing a computer module or sub-module. If you have the fan turn with the battery connected directly to it, then indeed it is the relay module. If the fan don't turn, then its the fan. You can fairly easily remove the fan and shroud from the unit and replace it with a new one. Myself, I like going to Advanced Auto and/or AutoZone or other good parts place since they will have in most cases, cut sheets for the step by step to follow. Some also will give you loaner tools for the job and you know you are getting what is needed without guessing. You can also, depending on your area, find a "You Pull It" type salvage yard where you go in, with tools, and pull the part yourself off one of the vehicles. Sometimes that is good or bad but can be very much less in price then paying list for a new or even refurbished one. If after all that, the darn fan don't turn, then the most likely would be a darn wire somewhere broken that is breaking the circuit. That is when you have the choices of take it to a shop or using the wire you had before, try to trace with that and a good multimeter, to find the broken wire and believe you me, those are buggers to find sometimes. Ahhhh for the old days when the fan was connected to the main drive shaft. Engine turns, fan turns...... if a clutch fan, it turns when ready to go. Still ya can still see what is what. Maybe that will hep ya some LOL William "Doc" Sheets,
Sometimes with these "new fangled" automobiles, I think that is the wrong gun to use. I am thinking more along the lines of the ones used when I stood quarterdesk watch in Navy..... a nice .45 Cal Auo Pistol sounds good to me LOL
migration_judge_roy answered 11 years ago
you sound like a real card, there Doc, NEWfangled...tell me about it...where's my accelerator cable? where's my speedometer cable? where are my pushbuttons on my AM radio? Where is the distributor? where's the vacuum advance?...these things have made fools of us!
migration_judge_roy answered 11 years ago
this lazer thermo-gun was quite useful back in '93 when we were trying to snoop out a cooling problem, after flushing the radiator knew where the blockages were with the thing~
My toolbox contains a very nice selection of hammers, large and small. One Crescent wrench and one screwdriver. That's all
I was having the same problem and found that the connection to the fan kept coming apart and I would have to snap it back together (clips broke)
migration_judge_roy answered 11 years ago
from experience Five bladed fans are quiet Six bladed fans are noisy...you should be a refrigeration technician to notice this~
migration_judge_roy answered 11 years ago
test the motor to find an open circuit or short...replace that one~
Chad_PIAJeep answered 11 years ago
I have similar issue but have tested it and found that the relay clip is not geting power to the #2 pin to turn the fan on. Any diagrams where I could check that wire closer to the PCM to see if the wire is broken somewhere between the 2 or maybe the PCM is not sending signal?
RubeGoldberg answered 6 years ago
Like the knucklehead that I am, I tried to outwit my Jeep by pulling one of the two fan relays and hardwiring the fan to stay on with a jumper (connected 87 to 30). It seemed to work like a charm as the fan kicked on immediately, but when I returned a minute later it was off. In a previous post “DocSavage” warned about potential “other issues including blowing a computer module or sub-module”. The Jeep parts manager suggested that I may have done just this. I’ve not connected to fan directly to the battery to check the motor yet, so until then I am wondering if anyone is familiar with the fan relay’s link to a computer module? How would I know if I’ve damaged a computer module? Can I just replace it or reset it in case I have damaged it? Thanks for any help!