Whitfield

I've been 3-weeks wading thru multi forum crap post searching for this information. YOU ROCK!!!!

My cherry bone stock 1984 SR-5 X cab 4-WD thanks you.

Never did find the malfunction, but taking it apart and ohming out all the leads / pins and reassembly fixed the temp gauge. Works like a champ now. Must have been in-between the (4) nuts and their connection on the back of the gauge as the (3) screws all read properly.

andykrow

Great write-up!

My gauge had the standard symptom of moving straight to the middle a second or two after startup.

I took it all apart, and noticed the nuts on the temp gauge were all a little looser than I would like. I could pretty much loosen them with my fingers. No busted wires on the transformer that I could see.

I cleaned up all the connections, snugged everything up and the gauge now reads in the middle, but takes a mile or two to get there

Sounds like a few folks have had a similar experience so I think it's a pretty good idea to clean the circuit board under the nuts, the washers and the nuts themselves. I gave it all a hit with some light sandpaper just to shine it up.

kc15842

This was by far the best write up I found on the sticky gauge. I disassembled and found nothing reassembled and still my inaccurate gauge. I was hoping that cleaning would help but no luck. It would be nice to find a source for a replacement temp guage. Thanks for the post.

Whitfield

If you get into diagnostics you can chase the connections and measure the coil winding resistance to see which gauge coil is not getting signal. A good volt ohm meter is worth its weight in new Yota parts here. I would also use caution cleaning the circuit board with sand paper (as some have a protective coating). Here on the High Humidity east coast the circuit board needs all the OEM moisture protection it can get. I was amazed to find how clean and corrosion free my original board was. I always prefer to prove a connection bad first.

A good TV repair shop could make quick work of the gauge fix ~ most with no instructions.

andykrow

Good to know! I would assume not as much of an issue out here in the dry mountain west, but we do have our humid days from time to time. I only hit the metal contact area, not the fiberboard, so hopefully I didn't cause an issue?

mct75

Hi everyone,

I got a SR5 cluster to swap into my 88 pickup, and when I put it in the needle went 1/3rd of the way up right away. I took it all apart and ohmed it all, and couldn't find anything wrong with it. However I tightened it all back up and now it seems to be working (knock on wood)

Some things to note for others doing this:

1. With the brown PCB in place, there's a 75 ohm resistor in the circuit
2. The terminal "T" isn't connected anywhere in the circuit, but it does have wires soldered to it
3. Watch out for the diode between two of the terminals. You may need to flip your leads to test across it
4. Measure your resistances from multiple areas of the cluster to isolate bad connections. I did everything from the edge connectors of the cluster
5. The ground and power (IGN) terminals aren't as important as the line from the sender, in terms of impedance

Here's some macro pictures I took. Again, none of my solder joints seemed to be broken. http://imgur.com/a/6rEfa

For reference, my Deluxe gauge maxed out at about a 3rd of the way up, and this one seems to go to almost half.

B-Fake

It works!!! Thank you thank you thank you! I didn't have any breaks in the windings, but taking it apart and making sure everything was clean and tight putting it back together seems to have done the trick. Great write-up, you freakin' rock!

4RunnerRogers

Nice write up and fix!

hambone5

nice i will be trying this tmrw thank you!!

VSerio707

I found the same issue

Thanks for the write-up with pics. I'll be sure to pass this post along to friends with the issue

MTNRACER51

Thanks for the writeup! Need to do this

MrNoName

Great informative post. It got me on the mend even thou my actual problem wasn't a broken wire. It was a ground problem. My temp gauge hasn't worked for around 10 years but I just now decided to fix it cause all my gauges went funky. The whole cluster started to act erratic, not just the temp gauge. Bit by bit I've got it all working again. First, I cant emphasize checking the grounds in the vehicle enough. A bad ground will effect the electronics in ways you wont believe. For me, with all electrical problems, I always start with the grounds. So,to start with, I removed and clean all the body, frame, engine and battery grounds. That made a complete grounded circle within the Vehicle and it ended up getting the cluster working again. Everything but the temp gauge. Like everyone else on here, the needle went half way up the gauge, even when it was cold. Still figuring a bad ground somewhere, and thinking it might be in the instrument cluster assembly, I removed that. On the back of the cluster, there are ground screws that screws into the back of the gauges thru the main circuit board. They are marked with a (-) symbol. After cleaning and re-tightening all of the screw on the back , I reinstalled the cluster thinking it was fixed. That did help but unfortunately it wasn't totally fixed. Now, sometimes it worked OK and sometimes it didn't. Being stumped, I started searching for other solutions. Finding some info on another post, there is a ground wire (black and white) that is located under the drivers side kick panel, near the fuse block. That is the ground for the instrument panel. Cleaning that didn't work either but now that ground is eliminated. Looking farther, and finding this post, I thought I might have a broken wire on the coil like the original post describes , seaming that it displayed the same symptoms. As it was, mine wasn't broke but the process led me to another discovery. The gauge has another ground point on it. Its one of the three little short post on the back of the gauge that holds that little circuit board on. Obviously, its the same post that is marked (-) on the main circuit board on the cluster. So, if anyone that does this same tear-down and doesn't find a broken wire on the coil, pay attention to a good contact on that ground post and that small screw on final assembly that has the (-) symbol. And if you've already done this procedure and didn't find anything amiss, and the temp gauge started working again after putting it all back together, chances are, removing and reinstalling these ground connections on the gauge fixed the problem. Like I stated in the beginning, I cant stress enough about the grounds. It may not be the problem but it can be a high probability. The biggest problem is finding all of them.

Clifford1990

Would this walkthrough be appropriate to replace the VSS1?

AGP

I'm sorry guys, I know that this may be the wrong thread but I can't find a way to start one, well, I hope somebody can help me with this issue, I have a 1995 4Runner 3.0 on which I just replaced the water pump, put a new thermostat and a new radiator in it.... The damn thing is overheating, the top part of the radiator is really hot but the bottom part isn't.... Can it be a faulty thermostat? Or a bad pump? Please help.....

Yotard

You have air in the system. You need to fill the engine with coolant through the upper radiator hose until it is full, then hook it up to your radiator and fill the radiator or in you case top it off. I had this same problem until I filled it that way.

AGP

Thank you, Yotard.... I'm going to do that tomorrow morning, thanks again...
i

moosecholok

I too have a guage that stays on cold, even though it's warm and has a good working thermostat. I have an old parts truck (1986 Toyota 4 WD 5 speed) that I'm parting out). I'll take that one out first. Need any parts?

ewong

Great Post

And great that is is sticky-ed

I just noticed that my temp gauge jumps to the middle when cold.
Its never been an issue as I also have a Autometer mechanical gauge installed. That one reads in real temperatures!

But now I know what I have to do
Or I can swap the gauge from another cluster that I have...

Heironymous Josch

Well, I'm going to be trying this soon. Great post.

KeepKool

In the middle of swapping my DLX gauge for a SR5 and found this issue on new cluster . Now I have a direction to take as far as troubleshooting goes . Thanks for the post , just what I needed right now : )