89 Caravan - Radiator Fan Not Running

Hi - thanks for any help. I started to get the message "maint required" on the left computer control module. When I 1st start the engine it says check engine but that part of the message goes away. When we got home last nite the engine is hot red light was on faintly. TOday I checked the radiator level and that was ok - I was leafing thru the owner manual and it said that the fan did not come on till the radiator fluid started to circulate - so I left the motor run ahile and the fan did not run. 1)Would the radiator fan not running be picked up by engine sensors on this 89 model - I tried trunning the key on 3 times (and holding it) but I could not get a code number to show - not sure if I was doing this wrong or if no number shows for this problem. 2)Could the problem be a fuse or a connector? Believe it or not - do not know where the fuse box is. 3)What is involved with changing the fan motor - I did not order it yet - they say I need the number off the shroud. ++++ I come here 1st - I fixed the fuel pump this spring - sure glad I changed the fuel filter (because of advise here) - it had regular gas lines instead of fuel injection lines and regular band clamps instead of fuel injection line clamps - and the regular lines were really cracked bad - could have busted anytime! :uhoh: Many thanks!!!!!

Yes, there are codes for cooling problems, but you have to count the flashes to get them:

If you wish to get know how to obtain the computer codes yourself, then the procedure is...

Chysler computer codes (80-95 Chysler's):

Chysler faults codes are stored in the computer for up to 50 ignition starts. Each code is two digits. Beware that some problems can generate multiple faults codes. The code's meaning (i.e. faulty sensor) can be found by doing a web search using keywords "Chryler computer codes".

To obtain codes: Turn the ignition key on-off-on three times (don't start the engine) will put the
computer into diagnostic mode. Watch the "check engine" light. Count the flashes for each digit which will be followed by a pause between digits. Two digits to a code. The end of the list is code 55.

To reset the codes, turn the ignition key on-off-on
50-55 times (don't start the engine).

The cooling system parts that usually fail are:

1. A temperature sensor switch located at the bottom of the radiator.
2. A relay to send power to the cooling fans.

Hi - I got the codes to work - I turned 3x before but did not subsequently just turn the key and leave it on (old paranoia from points burning) :screwy: Well - I just got the 55 code - that is what I got last spring when the fuel pump was out - that code is not any help to fix problems. The possible problems of a sensor switch at the bottom of the radiator or a relay that sends power to the cooling fan is quite interesting and any expounding of how to check the sensor switch under the radiator (does coolent run out when this is pulled) and the relay (location) would be helpful. The fan is $80 - if these are cheap, maybe replacing them 1st would be a better idea than replacing the fan until these possible causations of the problem are eliminated.

In rereading your problem, I am assuming that the vehicle gets hot after about 8-10 minutes and the radiator is HOT as well as the engine. If you had a stuck thermostat, you would overheat in about 3 minutes, but the radiator would be cold and the fans would not be expected to come on. The temperature gauge in the dash is seperate from the cooling fans and measures engine temperature. If you watch the temperature gauge while it is heating up, you'll see it pause at about normal operating temperature. This is the point the thermostat opens. If after another 5 minutes, the temperature begins to climb, the radiator is hot and the fans should come on then. If this is a cooling fan problem when the radiator is hot:

To debug the problem:

1. Find the temperature sensor switch. Disconect the connector and place a paper clip between the two sockets. Turn on your ignition. You have bypassed the switch. Expect your fans to run.

If the fans come on, it means the wiring from the relay to the fans is good. It also means your motor is good, The temperature sensor switch is bad if the fans don't come on when the radiator is hot.

If they don't come on, the relay, motor and wiring to/from the relay is suspect. I can't remember if there's a 30 Amp fuse involved for the cooling fan circuit, but I would check them anyway. It may have a fusable link intead of a fuse. This fusable link would be a wire from the battery going to the relay that would melt like a fuse under load.

2. To isolate, construct a jumper wire out of 12 gauge wire long enough to go from the battery to the fan motor. I make mine using a wire from a home extention cord with aligator clips attached. Attach one end to the fan motor at the proper spot and the other to the positive side of the battery. The fans should come on.

If the fans come on, the relay is bad or a fuse/fusable link is blown or in the wiring from the relay.
If the fans don't come on, the fan motor is blown.

Many thanks!!! I did run the caravan to the parts store nearby - for some reason I thought it was low on antifreeze - then ran it home - then left it idle awhile - the radiator was pretty hot --- no fan runnuing though. The dash temperature hot indicator is just an idiot light - there is not a guage. Tomorrow in the light I'll look into the car with the debugging instructions. Thanks again

You didn't mention engine size. My '94 3.0 litre (w/AC) has 2 fuses for the rad fan plus a relay, all in the power centre between the battery and the fender (black plastic box with 2 thick red wires leading into the front of it). My (Haynes) book shows 4 different circuits depending on engine size. On 2.2 and 2.6, there is a thermal switch in the radiator that controls the relay. On my 3.0 (also the 2.4, 3.3), the ECM controls the fan via the relay. The two fuses are labelled lo and hi speed. The lo speed fuse is a 25 amp small spade type and the hi speed is a large 30 amp cartridge type. On mine, the lo speed fuse blew but the fan still worked and the van didn't overheat. I guess the hi speed fuse is the one that counts. The fan bearings were going so the fan was harder to turn (too cheap to get a new one just yet, I took it out and oiled it - so far so good!). I guess the resistance was too much for the 25A fuse. The check engine light did not warn me but there is a code (35) for the radiator fan relay circuit (don't know what it takes to trigger that). Anyway, it could be the ECM can't detect all the stuff with the fan. Although everything is different for the new models, one of the fans on my 99 seized and killed the relay but the ECM showed no codes even when the engine got really hot and the check gauges light came on. After I replaced the relay and unplugged the seized fan it showed a code. It can tell if the fan(s) are there but it can't tell if they are running. Maybe the 94 is similar in that regard.

The big flat piece on top of the motor (air induction) says 3.0 litre - I thought the motor was smaller for some reason. I just saw it has 2 fans. The fan I saw not running was the passenger side fan - running the A/C this fan works - but the radiator fan is not working (even though I did not see this fan - I guess I would have seen it if it started running). There is a connector wire to the fan - I wrapped a wire a few times tight around the male end and touched the other end to the battery - so it seems the fan is out - there is 120,000 on the vehicle.

The low speed fan comes on when you turn on the AC. The high speed fan is controlled by the temperature sensor switch.

At the part store the guy there is mechanical - he said to touch both wires on the wire coming out of the fan - the fan did run this way. He could not see wires coming out of the bottom of the radiator - so he said the sensor could be somewhere else (I think this is what was refered to as a teperature control switch). I bought a $12 relay - that fit to 3 of the hookups but did not work.On the fender is mounted 2 pairs of relays. The one closest to the driver connector to the relay is different - the forward other 3 are the same. In addition to the 2 pairs - closer to the driver is some kind of other relay. So I am not sure which relay goes to the fan - there are 2 untested (both closest to the driver). The wires going from the fan go into bundles and I have not found in line fuses on the wires yet. +++ One thing related to what arobinso wrote - in front of (closer yet to the driver) the relays I wrote about (single one and 2 pairs) is a small round module with 2 real large wires going into it - they are not red - but seems like what he called a power center - would replacing this help the fan problem - if it is a bad power center it seems other things would not be working. Thanks again for any help!

I took the caravan to the dodge parts department. He took a wire right from the module to the battery - fan worked. He showed me the temp control sensor - on the engine (top of passenger side), pulling that off the fan came on. He explained that the fan comes on only when the engine gets real hot. So I ran it around town and then let it sit with the A/C on - fan did work. So the hot light came on the other night but not today - he thought could have been circulation problem - have to watch, if the hot light comes on again could be the thermostat. I asked about the maint required light that just started to be on - he says it comes on at 50,000 miles - about the only way to get it off is to hook it up to an engine analyizer. So an educational false alarm. Thanks everybody - I did learn alot. :rolleyes:

I seem to have similar problem
have checked things and am stuck finding coolant tem p sesnor switch that turns on fan ,,,Thanks CJ