need help with dccontrol fan

[daddystang]

Hey guys, does anyone have a dccontrol fan on their car? Here's my problem. I installed it today, and I'm pretty sure I followed the directions dead on, but I've got the temperature nob turned all the way down 145 degrees, but my temp is rising to over 190. The fan does turn on, but when I turn on the ac the fan turns a lot faster which I believe is at least 50% power. When I turn the ac off, the fan turns slower, and the temp is rising. I have the temp probe plugged into the radiator on the drivers side down near the lower radiator hose. Sorry for the long winded write up, but I wanted to try to give you guys all the info. Any help would be very appreciated. Brian B. if your on line I'd really like your input of knowledge.

Thanks so much.

Joe

 

[HISSIN50]

I'm sure Brian will chime in later.

Your install sounds good to me (probe placement, etc). Is the probe inserted all the way? A few folks have had issue with that.

Did you run down the troubleshooting on Brian's site? He's got some good stuff there, like measuring voltage across pins 1 and 2 (IIRC) to note probe function. I'd go off his site or his word over anything I might say.

Good luck.

 

[daddystang]

Thanks hissin50, I'll go back to his website and check the trouble shooting section. I'm pretty sure the probe is in all the way, but I'll check that again too. It sounds to me like it might be that it's not in all the way. It seems the fan just doesn't know that the temperature is up that high, not getting a good reading.

 

[AnthonyR23]

I may be wrong on this but am just curious... if your temp probe isn't measuring the coolant in the engine... but instead is measuring the coolant in the rad itself.. you will run warmer won't you... wouldn't you be better off having the temp probe going into one of the water jackets up top below the manifold.. like the one for your temp gauge..

eg. the fan will turn on earlier or on high earlier if the temp heats up faster..

That seems like it is your problem.... please correct me if I'm wrong..

 

[AnthonyR23]

In my opinion it is definetely a location problem...

 

[cobradvm]

I think your probe placement is fine - my DC Control probe is in the exact same location - low on the drivers side. I have my controller set to 180* and the controller keeps that needle right at 180 on my water temp gauge. The only suggestion I have is to double and triple check the jumper settings on the controller. I'm not sure about the knob thing - perhaps you have a different controller that doesn't have jumpers on it - but I know you had to be very careful about getting the jumpers set up right.
The idea about having the probe near the inlet is that you are controlling the temp of the coolant entering the engine.

 

[daddystang]

The one I have doesn't have jumper, but rather a knob that you turn from 145 to 215 degrees. Do you have your probe stuck all the way into the radiator that you can't see it. I've got it in, but it seems like it want's to fall out. I tried moving it higher on the left side of the radiator, but I think I should try moving it down closer to the hose like you suggest. I'll do that and update you guys. Stay tuned, and thanks guys for the help.

 

[HISSIN50]

The probe placement is indeed fine. That's one thing that separates the DCC unit from others on the market. Lower would seem (to me) to be better for a crossflow radiator.

The probe thing really is pretty important. Be sure it's inserted from the engine side. I seem to recall the circumference of the probe changes at it's bottom. I inserted mine till the base was flush with the fins. I had to carefully push the fins back against the probe after its insertion to keep it nicely in place. Use kid gloves with any fin pushing.

I have the rheostat as well - no issues.

Good luck.

 

[daddystang]

Thanks, I'll move it back down closer to the hose, and push the fins back around the probe. When you say your probe is pushed in untill the base is flush with the pins like the directions say, is the base the "ring" that runs around the probe about in the middle of it? (which is only about an inch long)

Thanks for the input.

 

[HISSIN50]

Thanks, I'll move it back down closer to the hose, and push the fins back around the probe. When you say your probe is pushed in untill the base is flush with the pins like the directions say, is the base the "ring" that runs around the probe about in the middle of it? (which is only about an inch long)

Thanks for the input.

Yeah, IIRC, my probe is inserted so the ring just barely sits in the fins (the ring kind of holds the probe in place).


I've seen a few threads where the issue was only a probe insertion issue, so it's amongst the first things I think of on threads like this. Another way to check probe function is with the testing across pins 1 and 2.

EDIT: His diagnostics for the probe are at:
Go to his mainpage,
Then FAQ,
Then the controller troubleshooting section, near the bottom of the selections.

Good luck.

 

[daddystang]

Thanks again. I read the troubleshooting last night, and saw the part about testing pins 1 and 2, but I'm not sure where the pins are. Maybe I missed it, I'll surely read it again, and do that tonight after I try moving the probe close to the hose, push it in further, and bend the fins around it to hold it in.

Thank you again.

 

[HISSIN50]

Thanks again. I read the troubleshooting last night, and saw the part about testing pins 1 and 2, but I'm not sure where the pins are. Maybe I missed it, I'll surely read it again, and do that tonight after I try moving the probe close to the hose, push it in further, and bend the fins around it to hold it in.

Thank you again.

As I recall, Pins 1 and 2 on the controller are where your temp probe connect (check your instruction's schematic real quick but I think I'm right). Just be real careful about testing in that area because if you bridge two terminals (the pair below 1 and 2 IIRC), you can fry the controller.

Good luck.

 

[DMAN302]

Also try running the underdrive jumper..I found with that my DCC unit held temp much better..it was overshooting to 200 when set at 180 but with the jumper in place there was no longer an overshoot. With the jumper the fan soft starts when ignition is on at 10% fan speed and ramps up easily maintaining my 180 setting. Just a thought.

 

[daddystang]

Just a question. What is the underdrive jumper? I know that some of the controllers set the on temp with jumpers, but mine has a knob that you turn. I do have an ignition wire that I think is optional to do the 10% turn on thing that you mentioned. If I connect that wire to a 12v source the fan will run at a minimum 10% power. Right now when I start the car it is off untill the temp starts going up. One funny thing is that when I started it last night, the temp guage in the dash went up a little over a 1/4 of the way which it says is above 130 degrees, yet my mechanical guage didn't move off 100 untill quited a few minutes later. Seemed wierd, but I don't trust that dash guage, because my mechanical oil pressure guage reads between 50 to 60 psi, and the dash guage drops to between a quarter and half way. Sorry, a little off topic..... I'm going to play with it tonight when I get home, and I'll update, and or ask for more help.

Thanks guys for the thoughts.

 

[DMAN302]

Check the website he shows the pins to use for the jumper feature for the u/d set up.

 

[DMAN302]

IIRC the pins are 13/14...DO NOT place a jumper between 11 and 12 on the unit.
http://www.dccontrol.com/index.htm

 

[daddystang]

Thanks DMAN302, but my controller doesn't have the jumper settings to set the temperature, it has the knob like a dial on a radio. Thanks for the input though.

 

[HISSIN50]

One funny thing is that when I started it last night, the temp guage in the dash went up a little over a 1/4 of the way which it says is above 130 degrees, yet my mechanical guage didn't move off 100 untill quited a few minutes later. Seemed wierd, but I don't trust that dash guage, because my mechanical oil pressure guage reads between 50 to 60 psi, and the dash guage drops to between a quarter and half way. Sorry, a little off topic..... I'm going to play with it tonight when I get home, and I'll update, and or ask for more help.

Thanks guys for the thoughts.

With your gauges, is the aftermarket gauge sending unit located in the stock location of the lower intake? And no tee fitting is used, right? Temp sending units do not like Tee's. If a gauge's sending unit is put in the t-stat housing, it will take awhile for the gauge to react because the stat is closed (that's why it's a bad location for an aftermarket gauge's sender). Just in case that applies......

Good luck.

 

[daddystang]

The mechanical guage is installed in the lower intake toward the back in one of the free openings that's usuallly blocked off.

Well, I moved the probe down about 1 inch from the bottom corner of the radiator, and about 1/4 inch from the side. I connected the ignition wire to a key on source which I forgot to do yesterday, but still the same problem. I turned the knob on the controller to where I thought 175-180 degrees would be, and the fan is spinning, but not real fast. My guage got up to right around 190 so I turned it off. I tried turning the temp set knob all the way down to 145 to see if the fan would pick up speed, but it didn't. Then I turned the air on again, and the fan really picked up speed. I'm stumped as to why it's not spinning faster to cool the temp down.

Just some additional info: The upper radiator gets very firm as if it's building up pressure which is a good thing I think. I made sure the probe is in the radiator good and tight.

I haven't tested pins 1 and 2 yet, because I'd have to un-mount the fan, and I guess I'm trying to avoid taking it apart.

What am I doing wrong hmmmm.

 

[GreatWhite]

If it's the same fan controller I have, they come set to work with a 180* thermostat. That is, the fan comes on when the temp probe is reading 180 or higher. I have my probe right next to the bottom rad. hose as close at it can be. I haven't had a problem with it since the day I installed it.

Which model do you have?

I know you can use jumpers to change it to come on in different intervals too. Like instead of 180, it could come on at 172 or 188, I think. Not sure but I'm almost positive it's like 8* intervals.