$6.87 solved my overheating problem

[aggie2000]

Okay, it’s no miracle solution, but I just wanted to post my experience for the other novices out there. My 2002 RT/10 all of the sudden started overheating during a “spirited” low-speed drive through the hills: low speed/airflow and high revs. The overflow tank started puking fluid (not too much), and I could hear the coolant boiling inside the radiator. Temp spiked to 250. I cooled it down a bit and drove home in the highest gear I could muster to minimize revs and temps.

I spent 3 full days pouring through the forums, reading about which aftermarket radiator is best, how to “burp” a viper cooling system, etc. After burping and seeing no change, I decided to go back to the basics. If it cools when I’m hauling a$$ but not when I go slow, it’s probably an airflow issue. Radiator fins, etc. looked fine, so I looked at the next possible culprit: IS THE FAN EVEN TURNING ON?!? Well, in fact it was not turning on; I used my super-sleuth skills to comb through the wiring diagrams in the manual and trace the problem to a failed Radiator On/Off Relay. AutoZone didn’t have a specific relay for the Viper, but the helpful attendant found the same relay on the shelf (listed for a different car). Anyway, $6.87 later, no more overheating problem.

Moral of the story is: always check the basics first before you start digging into more complex problems. Novice mistake, but we live and learn. And thankfully I learned for less than seven bucks!

 

[JonB]

Good Catch...a DRB at Dodge would reveal it, too. You could have swapped it with any number of relays, including 3 in the car, just to verify.

 

[Chuck 98 RT/10]

Good catch. I may have the same problem with my GTS.

 

[Dom426h]

Are we talking about the relay that is located under the hood in the fuse box above the PCM ?

looks something like this?

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guess i'll swing by autozone as well and grab one to keep in my trunk, thanks for the heads up

So what would cause the relay to fail? If yours dies again, than maybe there is a bigger prob in the electrical system...

 

[99 R/T 10]

Have a part number thru autozone for that relay?

 

[MattInNC]

Have a part number thru autozone for that relay?

Mike - I picked up a spare one a few weeks ago. I'll find the box and post the number in a few.

 

[MattInNC]

Brand is "Niehoff"
Letters / Numbers on box are:
BWD
R3177
RL36621

I got mine at O'Riley's
Zip Code Select | O'Reilly Auto Parts

 

[GTSnake]

Way to go. That's part of being a Viper owner is doing a lot of your own diagnostics. This forum helps a lot but sometimes you're on your own if you don't want to pay dealer prices.

 

[aggie2000]

Thanks for the feedback guys. I'm just glad I didn't have to drive an hour to the nearest Dodge dealer and pay him $150 labor to sell me an overpriced $7 relay!

JonB is right on the money - there are 4 identical relays in my '02 RT/10 in the same place (Power Distribution Center under the hood, driver side) that control different things (Rad fan on/off; Rad fan speed; ABS something or other; and I forgot the last one). Easy to swap 'em out to determine if it's your prob or not.

Reference Dom's pic, my relays are "slightly" different, but same general design: cube with 5 flat prongs on one side. Amp ratings(?) were different for my prongs, but that may be just because it's a different year than Dom's. Just make sure the new relay matches with the same #s as the circuit diagram on the side of the old one.

Easy enough to just take the part in to your local parts store and they'll hook you up - it's a somewhat common relay, so I'm told. Anyway, at Autozone my replacement relay was a Duralast part, #19273 on the box.

 

[aggie2000]

Oh, and one last comment:

I'm all for doing my own diagnostics, saving a buck, and learning more about this amazing car. But, I wouldn't even know where to begin if it weren't for this forum and the wonderful people involved in the VCA.

Thanks everyone for making Viper ownership such a rewarding experience!!

(my next task is to learn how to post pics )

 

[Rickman6]

I couldn't agree more to your statements....and pls. let me know how the you posts pictures ( once you figured out...I've givin' up..

Brgds

 

[darkostoj]

my condenser fan turns on when i put the a/c on...but i also think my main fan isnt turning on. Is it the same fan? Isn't it supposed to run for like 3 minutes after you shut off the car? Mine isnt doing that. I don't over heat, but the temps get around 220-230 if i'm sitting in traffic on a super hot day...it was real bad when i was on the dyno a couple months ago...after one pull the temp would shoot up to 230ish right after the pull.

 

[JonB]

Thanks for the feedback guys. I'm just glad I didn't have to drive an hour to the nearest Dodge dealer and pay him $150 labor to sell me an overpriced $7 relay!

JonB is right on the money - there are 4 identical relays in my '02 RT/10 in the same place (Power Distribution Center under the hood, driver side) that control different things (Rad fan on/off; Rad fan speed; ABS something or other; and I forgot the last one). Easy to swap 'em out to determine if it's your prob or not.....

My favorite phrase, THANKS! Not to mention another relay in the trunk.

SOME Relay TRIVIA:

I was helping with Pace Car duty at Sebring in 1997.... FIA Championships. Viper was the Official Pace Car...Sebring was the parade car (Official car) When I got there, THE PACE CAR HAD DIED ! PARKED off behind the pit-row. So FIA were using the Sebring as a pace car, gutless as it was...YUCK. We volunteered em a VCA member's car (Gary Lashinsky) but for lack of signs, lights, no deal. DANG...... "Can I take a crack at a fix?" I ventured? I showed em my ICSCC Pace Car license, and Iwas decked out in Dodge gear.... they tossed me the keys.

I popped the hood and trunk and swapped relays for Horn and Fuel, primed the bleed-down with 3-4 key cycles, and and vvvVVVVROOOM! The Viper roared back to life. FIA was very happy! My reward was getting to drive it for parade laps before the event, and I led the VCA from their corral for a couple laps....The Viper started and re-started several times, and was put BACK in service by FIA for the race! ( I then realized I was just a guinea pig for those parade laps! A balky starter = a BAD Pace Car! )

Chrysler clinched the FIA Manufacturers' Title that day..... a personal goal of Bob Lutz. We got a champagne shower in Victory Lane. Chrysler went on to clinch the Driver title 2 weeks later at Laguna. (Toyota Pace Cars in 1997...Mazda now) VCA was IN FORCE at both, and I got some Pace Car seat time at both.... Great Fun, fond old memories.

 

[jay01m]

Ok guys, I'm resurrecting this thread to find out where the heck these fan relays are at on my 97 GTS. I have a continuing cooling issue and need to try to fix this. I have a brand new radiator fan installed, I've had my radiator re-cored to a triple core radiator, and it has been properly burped (the upper radiator hose is full of coolant). If there's another way to tell if my radiator has been properly burped, I'm all ears, but as far as I know I'm good to go with that.

Where are these relays at? I just bought new relays and want to replace the old ones. Can someone post a pic or explain to me where they are at please. Thanks!!!

Jason
Hampton Roads VA

 

[97GTS]

They are under the hood, driver side in the "box". Pop the cap.


Ron

 

[97GTS]

The square box on my 97 is where the relays for the fan are. They look different than the ones shown.



Ron

 

[jay01m]

Thanks 97GTS, now I know I'm not going crazy. I guess I've been staring right at them the whole time. Not the same as the ones posted on here though. Now that I know I can replace them. Hope that makes the difference.

 

[97GTS]

Went out and pulled mine because my temp is high as well. No diagram on the relay just numbers. Got my OHM meter out and couldn't figure out which terminals are hot so gonna just buy 2 relays, replace them and see if it helps.

$14 is cheap. If it doesn't work then I will have 2 spares.




Ron

 

[jay01m]

Yup, I'm doing the exact same thing. This overheating is starting to get on my nerves.

If you find yourself still overheating, consider this...

Be Cool 75059 - Be Cool Electric Fans - Overview - SummitRacing.com

I ordered mine and got it in last week. I may install it even if the relays fix my problem anyways. Its a low profile fan that should fit perfectly in front of the radiator with some mounting brackets. If I put it in I'll post how it went.

Went out and pulled mine because my temp is high as well. No diagram on the relay just numbers. Got my OHM meter out and couldn't figure out which terminals are hot so gonna just buy 2 relays, replace them and see if it helps.

$14 is cheap. If it doesn't work then I will have 2 spares.

Ron

 

[jay01m]

Ron - Are you sure they are on the driver's side. I wasn't sure and after diving into my service manual last night, it says the relays for the fan are under the blower housing on the passenger side. Haven't had a chance to look yet, but will do so today.

They are under the hood, driver side in the "box". Pop the cap.

Ron

 

[past ohio]

I have an old Chevy that had a constant warming problem ( radiators back then weren't quite good enough) and I bought a bottle of "water wetter" because a drag racer told me about it, my temperature seemed to come down about 5 degrees...anyone tried it in their Viper, I know Vipers generally push the upper limit on the temp gauges...

 

[97GTS]

Ron - Are you sure they are on the driver's side. I wasn't sure and after diving into my service manual last night, it says the relays for the fan are under the blower housing on the passenger side. Haven't had a chance to look yet, but will do so today.

Yes, on my 97 I pulled both. Price is about $16 on these. There are 2 boxes with relays on the driver's side, right above the main computer. One ( the long one) points to the positive connection that has a red cap on it. In front of the red cap is a square box with 3 relays.


Ron

 

[dave6666]

are 2 boxes with relays on the driver's side, right above the main computer.

The fan relays for the OE fan are here. The black one is the on-off relay, and one of the others is the hi-lo speed relay. Just flip the cover over for the legend. Oh, and the reason I have a relay that says Ford on it in my Dodge is that I have a bunch of relays from a burned up Super Duty panel, and the fan on-off relay in my car is just a dummy to prevent CEL's. I designed a dual pusher fan assembly and all 3 fans are now controlled by a stand alone thermostat. The set point from the PCM still controls other functions but not my fans.

You must be registered for see images

 

[jay01m]

Dave and 97GTS - Thanks for clearing it up. Now I'm wondering why my service manual says it's on the passenger side. Time to go to the store.

Jason

 

[Red Shift]

The fan relays for the OE fan are here. The black one is the on-off relay, and one of the others is the hi-lo speed relay. Just flip the cover over for the legend. Oh, and the reason I have a relay that says Ford on it in my Dodge is that I have a bunch of relays from a burned up Super Duty panel, and the fan on-off relay in my car is just a dummy to prevent CEL's. I designed a dual pusher fan assembly and all 3 fans are now controlled by a stand alone thermostat. The set point from the PCM still controls other functions but not my fans.

You must be registered for see images

Is that a catch can on the left side of the photo? That looks cool with the Viper logo. Did you have a stencil to paint it on?

 

[dave6666]

Is that a catch can on the left side of the photo? That looks cool with the Viper logo. Did you have a stencil to paint it on?

Had it powder coated RAL3001 and then a sign shop cut the vinyl decal.