My coolant temperature gauge in my '88 4Runner V6 is not working. It does not move whatsoever. I've checked the ECM for voltage (~1 volt), the wires to the ECT sensor for voltage (~5 volts), and the ECT sensor for resistance. The gauge does not even move when I short the wires going to the ECT sensor. I'm hoping this is not a gauge problem. Could it be faulty sender(s) or connections to sender(s)? Where would they be located? Thanks.

 

Typical, need some more information, Veh, year, motor,

 

Your temperature gauge has its own sensor which is located in the back of the intake. Get a wiring diagram to see which one it is. When you do find out, take the pigtail and ground it. They gauge in your truck should peg to HOT. If it doesnt then you need a new gauge. If it does you need a new sending unit. The ECT is for the computer only and not the gauge.

James

 

would someone be kind enough to take a picture of the temperature sender behind the intake? if that's not possible, could someone tell me what the colors of the wires going to the sender are? there's a few wires back there and i want to be sure i'm working with the right one.

 

Get a wiring diagram. Maybe if you search you can find it here or on other Toyota websites. Its hard to take a pic because of where it is. I can try tonight for you.

James

 

is THIS the Coolant Sensor on 3.0l V6 Engines?? (Mine is an 89)

 

the coolant sensor for the temp gauge I mean.

I tired grounding the wire that went to this, and it stayed at 1/2 gauge. It did not peg. (i've been having a problem that the temp always seems to stay at 1/2 gauge, even when COLD!!)

 

according to the '88 and '93 FSM that looks like it's the one, though i haven't confirmed it myself. my temp gauge works only once in a while.

 

what are the other two plugs on this for ?
i have a after market temp guage i would like to install and i am looking for a spot to place it. or can i put a brass T on it.

 

i had the same problem and it ended up being a bad ground

 

Thanks for the reply. Had this figured out a few weeks ago tho.

 

Death, the one you have circled runs the gauge on the truck, the one to the left of it is the engine temperature sensor that tells the ecu the engine temp, to control the injectors. When I put my mech. gauge on, I got an adaptor, and took out the sensor you have circled. Screw the adaptor in, then screw in the end of the gauge.....Waalaa nice new gauge, that is much, much, much more accurate than the factory gauge. If you have any other questions on gauges let me know, I also have the oil, and amp gauge. I just got these here... http://www.sunpro.com/product_detail.php?pid=16316

I installed them in the din slot under my radio, I can take some pics to if anyone wants to see them installed.

 

what was wrong in your case? was it the gauge itself?

 

Yes, it was the gauge itself. I followed the FSM testing procedures, and determined it wasn't the sensor, or the wiring. The tested the gauge by grounding out the wire and it did not respond, so I knew it was the gauge. 4Runner runs cool and calm now.