87 4runner 22re Temp Gauge fix, finally!
02-26-2013, 10:51 PM
#21
There is a thread here with links for lots of manual downloads and online type.
93 FSM Link
Could you hop over to Wuffa's thread that would keep us all on the same "page" a lil better. This thread is "loose connections causing gauge reading wrong". It's unlikely yours are loose since you already tightened them. Although they may still be dirty, you can use generic type rubbing alchohol, aka IPA, It's maybe a bad idea to clean them with an abrasive but can be done in moderation, eg becareful not to take to much off it's really really thin.
You need to read the voltage with the harness attached, other wise it will be zero
The temp guage sender is the one in the middle of the lower intake right below the cold start injector.
93 FSM Link
Could you hop over to Wuffa's thread that would keep us all on the same "page" a lil better. This thread is "loose connections causing gauge reading wrong". It's unlikely yours are loose since you already tightened them. Although they may still be dirty, you can use generic type rubbing alchohol, aka IPA, It's maybe a bad idea to clean them with an abrasive but can be done in moderation, eg becareful not to take to much off it's really really thin.
You need to read the voltage with the harness attached, other wise it will be zero
The temp guage sender is the one in the middle of the lower intake right below the cold start injector.
02-28-2013, 08:26 AM
#22
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Ok so I have a 82 pickup 4x4 and today I'm going to work and the temp gauge never moved at all, yesterday it was working but today nothing. Does this sound like a sensor or what and like I said it didn't fluctuate any. Thanks
10-28-2015, 03:23 PM
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I can't find the ground! can anyone help me? I did everything else and I'm sure it's the ground, just can't find it. :/
Everyone, haven't been to this board in a while since I sold my other 4runner. But, I missed it so much I bought another one, an 87 4runner with the 22re. Since then, the dash temp gauge has been both inaccurate and crazy, wildly jumping from cold to hot to normal and back for months. After searching everywhere for a solution, I finally decided to get out my oscilloscope and find the real problem.
So, here it is for anyone that is interested:
If your 22re temp gauge is acting funky or is plain wrong, here are the steps to fix it. First, check the temp sender on the intake manifold between the intake runners, next to the block. Be sure that it reads a resistance to ground between 56 ohms and 500. The resistance will change dependent on the ambient temp and the engine temp. If that is working, check the actual connector on top of the sender to make sure that its not corroded. Replace if necessary. Next, if the gauge still does not work, you are going to have to remove the cluster. No big deal, really, it just takes a bit of doing. You will need a drill with a phillips bit on an extension and start removing the screws the hold the upper and lower dash together. When those panels are taken off, reach your hand (or find someone with a small hand) to reach behind the sub dash behind the cluster and unplug the speedo cable. Hint: there is only one clip and its on the top. Push it down toward the floor and the cable should come off easily. Next, unplug the plugs on the cluster and take it out. Then, take the cluster and gently set it down upside down on your workbench on a towel (so you don't break the mileage reset button) and look at the printed flexible circuit board on the rear of the cluster.
The screws on the cluster were not mounted from the factory using any type of locktite or anything to hold them in place. If your truck was in a hot climate (like 115 degree summers in modesto, CA) most likely the screws have loosened due to thermal cycling, making intermittent contact with the flexible PCB. When there is intermittent contact with the ground trace on the gauge, the device "searches" for a ground through any other connection-- this just happens to be the sender wire, going through the sender and making contact with the block at a substantially higher resistance than if the gauge grounded itself through the ground trace on the PCB. This is evidenced by toyota owners who have to punch the dashboard to make the temp gauge work, or when you notice the temp gauge jump to normal temp when the engine has been running less than 2 minutes.
To fix the problem, simply loosen the screws, spray contact cleaner on the flexible PCB and then tighten the screws again. Most likely, you will notice that the screws were barely attached when you removed them, owing to the fact that they loosened over time and there was no way to tighten them without removing the cluster. If you are bored, go ahead and tighten the rest of the screws on the cluster and watch all the other gauges function like new. There is the possibility that the entire cluster ground for the dash has also corroded. That is located on the driver inner fender underneath the kick panel garnish piece. Ground wires in 80's toyotas are white/black stripe-- so they should be easy to find. If this ground is loose or corroded, simply repair and retighten it and you should be all good.
Good luck and glad to be back![/QUOTE]
Everyone, haven't been to this board in a while since I sold my other 4runner. But, I missed it so much I bought another one, an 87 4runner with the 22re. Since then, the dash temp gauge has been both inaccurate and crazy, wildly jumping from cold to hot to normal and back for months. After searching everywhere for a solution, I finally decided to get out my oscilloscope and find the real problem.
So, here it is for anyone that is interested:
If your 22re temp gauge is acting funky or is plain wrong, here are the steps to fix it. First, check the temp sender on the intake manifold between the intake runners, next to the block. Be sure that it reads a resistance to ground between 56 ohms and 500. The resistance will change dependent on the ambient temp and the engine temp. If that is working, check the actual connector on top of the sender to make sure that its not corroded. Replace if necessary. Next, if the gauge still does not work, you are going to have to remove the cluster. No big deal, really, it just takes a bit of doing. You will need a drill with a phillips bit on an extension and start removing the screws the hold the upper and lower dash together. When those panels are taken off, reach your hand (or find someone with a small hand) to reach behind the sub dash behind the cluster and unplug the speedo cable. Hint: there is only one clip and its on the top. Push it down toward the floor and the cable should come off easily. Next, unplug the plugs on the cluster and take it out. Then, take the cluster and gently set it down upside down on your workbench on a towel (so you don't break the mileage reset button) and look at the printed flexible circuit board on the rear of the cluster.
The screws on the cluster were not mounted from the factory using any type of locktite or anything to hold them in place. If your truck was in a hot climate (like 115 degree summers in modesto, CA) most likely the screws have loosened due to thermal cycling, making intermittent contact with the flexible PCB. When there is intermittent contact with the ground trace on the gauge, the device "searches" for a ground through any other connection-- this just happens to be the sender wire, going through the sender and making contact with the block at a substantially higher resistance than if the gauge grounded itself through the ground trace on the PCB. This is evidenced by toyota owners who have to punch the dashboard to make the temp gauge work, or when you notice the temp gauge jump to normal temp when the engine has been running less than 2 minutes.
To fix the problem, simply loosen the screws, spray contact cleaner on the flexible PCB and then tighten the screws again. Most likely, you will notice that the screws were barely attached when you removed them, owing to the fact that they loosened over time and there was no way to tighten them without removing the cluster. If you are bored, go ahead and tighten the rest of the screws on the cluster and watch all the other gauges function like new. There is the possibility that the entire cluster ground for the dash has also corroded. That is located on the driver inner fender underneath the kick panel garnish piece. Ground wires in 80's toyotas are white/black stripe-- so they should be easy to find. If this ground is loose or corroded, simply repair and retighten it and you should be all good.
Good luck and glad to be back![/QUOTE]
04-13-2020, 03:31 PM
#26
I just went through this as well. I verified all the pin outs on the A B and C connectors were correct according to the FSM. Grounds were strong, Keyed positive was good. I verified continuity all through the printed circuit on the back of the Combination Meter. My temp and fuel gauges were checking out "close" to FSM resistance specs. Still nothing at the senders with an analog(needle) style meter. I then pulled the gauges from the cluster and and tested them removed and they tested perfect. I did notice the copper under the nuts was nice and shinny. Everything sticking out the back of the cluster not so much. So I cleaned the washers and nuts with some 400grit wetdry sand paper and cleaned up the studs with a small stainless wire brush. Then gently cleaned the printed circuit where the nut and washers contact it. I have a couple old pens with those gritty white erasers on them. I like to use those to clean up delicate electrical contacts. I put it all together and both gauges are working.
Take care and good luck with your projects.
Take care and good luck with your projects.
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old87yota (04-13-2020)
04-13-2020, 05:16 PM
#27
I just went through this as well. I verified all the pin outs on the A B and C connectors were correct according to the FSM. Grounds were strong, Keyed positive was good. I verified continuity all through the printed circuit on the back of the Combination Meter. My temp and fuel gauges were checking out "close" to FSM resistance specs. Still nothing at the senders with an analog(needle) style meter. I then pulled the gauges from the cluster and and tested them removed and they tested perfect. I did notice the copper under the nuts was nice and shinny. Everything sticking out the back of the cluster not so much. So I cleaned the washers and nuts with some 400grit wetdry sand paper and cleaned up the studs with a small stainless wire brush. Then gently cleaned the printed circuit where the nut and washers contact it. I have a couple old pens with those gritty white erasers on them. I like to use those to clean up delicate electrical contacts. I put it all together and both gauges are working.
Take care and good luck with your projects.
Take care and good luck with your projects.
04-14-2020, 11:36 AM
#28
Registered User
Those white, gritty, pen erasers are actually too rough to use on electrical contacts, especially on printed circuit cards, like the back of the gauges. Easy to "erase" right through the contact, leaving a break in the contact. You should ONLY use the pink, pencil type erasers. That's the only one I'll ever use.
Another handy thing is a substance I only know as "ruby paper". Essentially, it's paper infused with that pink, jeweler's rouge, cleaner. It works extremely well removing corrosion from electrical connectors and contact. If you can find jeweler's rouge, you can rub some onto a cloth, or rough paper, and use that. Even a cotton Dremel bit will work, with jeweler's rouge, but be very careful about the pressure and speed you use. Light pressure, slow speed.
Have fun, all!
Pat☺
Another handy thing is a substance I only know as "ruby paper". Essentially, it's paper infused with that pink, jeweler's rouge, cleaner. It works extremely well removing corrosion from electrical connectors and contact. If you can find jeweler's rouge, you can rub some onto a cloth, or rough paper, and use that. Even a cotton Dremel bit will work, with jeweler's rouge, but be very careful about the pressure and speed you use. Light pressure, slow speed.
Have fun, all!
Pat☺
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