HELP PLEASE, 02 GTS fan not opperating

[bumblebee]

have a 02 GTS with Roe supercharger backed with VEC2. My cooling fan does not opperate...unless I turn on the AC. I located and checked RELAYS and they are good. WOuld it be my PCM or VEC2 If so, I rather not replace and try too use the ROE Fan control switch they offer if that would fix the proble..not sure.

Thanks for any suggestions.

 

[dave6666]

Sending unit?

 

[bumblebee]

Sending unit?

i thought the fan operated off the guage and PCM. Guage still works fine. If there is a sending UNIT where would it be located. I located the coolant temp. sensor (driver front head).
Thanks.

 

[whitebluevipe]

from what i understand there is a sending unit that the pcm works off of. temp guage is seperate. i am currently going through this problem myself.

 

[dave6666]

The sending unit give info to the PCM which controls the fan. It is on the driver side head at the front. That's the one.

 

[bumblebee]

The sending unit give info to the PCM which controls the fan. It is on the driver side head at the front. That's the one.

OK...i located it but from what I read..they never go bad. ANy idea what the part number is or a good retailer for viper parts besides Dodge parts?

Thanks.

 

[dave6666]

OK...i located it but from what I read..they never go bad. ANy idea what the part number is or a good retailer for viper parts besides Dodge parts?

Thanks.

If you were reading here then, um, yes you would find that they do occasionally go bad. It is a cheap starting point for troubleshooting your problem.

 

[bumblebee]

I'm a new viper owner..were is a good place for parts?

 

[dave6666]

I'm a new viper owner..were is a good place for parts?

For a sending unit I would just find a local Dodge service center (parts counter).

 

[uvbnbit]

+1
Stick with genuine Mopar parts when it comes to sensors.

 

[bumblebee]

would I get a code if the sending unit went bad?

 

[dave6666]

would I get a code if the sending unit went bad?

Steam coming out the hood vents? Indian style code?









Seriously though, from the people that have posted theirs went bad, I don't recall anyone ever mentioning a code.

 

[bumblebee]

Ok...I checked coolent,Good. I checked the relays, Good. I inspected and cleaned all 3 connectors into PCM, Good. I found this..I unplugged the Coolent temp sensor located on the driverside head. The fan runs with AC off. I Plugged the sensor back in and guess what..fans turned off. Just too double check, I unplugged connection once again and fans turned on. So...I'm thinkin bad coolent temp sensor. What do you all think? Unless the PCM is seeing an open connection and automatically kicks on fan. I still have no code with connection made, but with connection open i get code(of coarse). I would still think if sensor was bad I would get a code
Thanks and good talking to you today Tony

 

[1TONY1]

Ok...I checked coolent,Good. I checked the relays, Good. I inspected and cleaned all 3 connectors into PCM, Good. I found this..I unplugged the Coolent temp sensor located on the driverside head. The fan runs with AC off. I Plugged the sensor back in and guess what..fans turned off. Just too double check, I unplugged connection once again and fans turned on. So...I'm thinkin bad coolent temp sensor. What do you all think? Unless the PCM is seeing an open connection and automatically kicks on fan. I still have no code with connection made, but with connection open i get code(of coarse). I would still think if sensor was bad I would get a code
Thanks and good talking to you today Tony

Sensor would be a cheap start. After that, bad or broken wire and plugging the sensor in is making a connect to a short.

 

[bumblebee]

Sensor would be a cheap start. After that, bad or broken wire and plugging the sensor in is making a connect to a short.

yeah...probably right with the bad wire. I'll do the sensor but I thin its goin to be a wire and finding that is goin to be great fun!

Question, after changing the sensor I may loose a bit of antifreeze. what kind should I replace with?
Also, should I just drive it around for a while and let it "burp" or "Bleed" itself.

Thanks for the help,
Troy.

 

[dave6666]

Just checked the Powertrain Diagnostics Procedures Manual on my '01 and there are a few codes for the fan relays but none for the sensor.

 

[bumblebee]

Just checked the Powertrain Diagnostics Procedures Manual on my '01 and there are a few codes for the fan relays but none for the sensor.

Ok..thanks Dave6666 for your help. I'll order the sensor tommorrow and keep you all posted

 

[bumblebee]

Sending unit?

Just installed new Mopar Sending unit and of coarse no good results. Fans still do not opperate
what next....................

thanx

 

[dave6666]

yeah...probably right with the bad wire. I'll do the sensor but I thin its goin to be a wire and finding that is goin to be great fun!

What makes you think that there might be a wiring problem?

 

[bumblebee]

What makes you think that there might be a wiring problem?

i actually don't think it is a bad wire. this car only has 19K miles and has not see many rainny days...just trying too narrow down the possibilties.....any more suggestions??

 

[dodgefever]

Ok...I checked coolent,Good. I checked the relays..."

How did you check the relays? I had this exact problem a couple of weeks ago on my '99 GTS, and I thought I had checked my relays to be good. It wasn't until I swapped the 2 relays that I popped a code telling me I had a fan issue. I took the relay to Advance Auto, where they cross referenced it to one they had in stock for $10. I put that one in and have had no problems since. Fan comes on without the A/C on just as the temp. crosses about 200, and shuts off just below 190.

 

[bumblebee]

Ok...I checked coolent,Good. I checked the relays..."

How did you check the relays? I had this exact problem a couple of weeks ago on my '99 GTS, and I thought I had checked my relays to be good. It wasn't until I swapped the 2 relays that I popped a code telling me I had a fan issue. I took the relay to Advance Auto, where they cross referenced it to one they had in stock for $10. I put that one in and have had no problems since. Fan comes on without the A/C on just as the temp. crosses about 200, and shuts off just below 190.

the fan does not come on until over 200?seems high.
Yeah,i swapped the relays..which it was that simple. my 02 had 4 in that panel. swapped them all around and still no luck

 

[Tim]

I have a 2002 RT10 that had a similar problem and the wiring harness going into the fan was bad and this was changed as a unit on warranty with 25, 000k on it.

 

[bumblebee]

i Have A 2002 Rt10 That Had A Similar Problem And The Wiring Harness Going Into The Fan Was Bad And This Was Changed As A Unit On Warranty With 25, 000k On It.

I Would Not Think The Harness Into Fan Because The Fan Does Work With Ac On And Does Also Work When Unplugged From Temp Gauge Sending Unit. Computer Must See An Open Circuit And Kicks The Fan On.

 

[dave6666]

the fan does not come on until over 200?seems high.

Then how do you know that your engine just isn't getting hot enough?

 

[bumblebee]

Then how do you know that your engine just isn't getting hot enough?

i believe i turned the car off when gauge was @ 225...i'll try again today

 

[dave6666]

i believe i turned the car off when gauge was @ 225...i'll try again today

If you were in the car driving at that point you'll never hear the fan come on. Unless you have a girlie sounding exhaust...

 

[bumblebee]

If you were in the car driving at that point you'll never hear the fan come on. Unless you have a girlie sounding exhaust...

never drove it...just let it idle in garage. had the hood popped. no fan spinning

btw...my car is far from quite

 

[dave6666]

By the time your gauge gets to that last mark before "the end...," your fan should come on. Mine comes on between the last of the 3 center marks and the 220/225 mark. Whatever that damn mark is. Shuts off about halfway between center marks 2 and 3. I'd let it go smidgen higher just to check things. Once it fully crests that last mark before d-day then yes shut it down and have a floor fan ready to give the beast comfort.

 

[Rock Morgan]

My 97 GTS is doing the exact same thing. I added coolant to the system and let it idle in the garage. I had the heater on and everything was fine. It never got over the third mark. I then turned the a/c on to see if that would make it get hotter. It got about 5 degrees warmer, and I turned the a/c off to see if it would cool back down. When I turned the a/c off the fans quit running. I swapped the relays for the starter and the high speed fan. Nothing changed. I assumed the relay on the left back was the high speed, and swapped it with the starter on the back right. I did not check the front left, and the front right is open.