Rudi,
I'm having a similar issue.. 12-13 volts when sender not hooked up, ~10 volts when sender is hooked up (should be 5V, right?).
Clusters, Gauges, Speedo & Odo meters
- Thread starter bj40green
- Start date
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Rudi,
I'm having a similar issue.. 12-13 volts when sender not hooked up, ~10 volts when sender is hooked up (should be 5V, right?).
bj40green
Tssss, tssss
- Thread starter
- #562
Yes. If you touch that wire to ground your gauge should go to H. Don't do this too long or your gauge will burn up. The engine must be running for this test otherwise the VR is not activated by the oil pressure.
Ask the help from somebody. One touching the wire and the other reading the gauge.
If so, your sender is defective. The internal VR is not working.
Rudi
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Hi Rudi,
Thanks for the great post. I have a 75 FJ40 and my fuel gauge was previously always pegged on full. I read through these posts which helped me tremendously. Last week, I ended up pulling the fuel sending unit and testing it and it reads 12 full and 120 empty. I was getting the same reading at the connection at the cluster. I ended up pulling the cluster, pulled the fuel gauge and did the multimeter tests you listed on page 3 and came up with what you said they should be: Left to right: 25 ohm, Top to right: 25 ohm, Left to bottom folded lip (ground): 113 ohm, Right to bottom folded lip: 138 ohm
I ended up reassembling everything and the fuel gauge started working, although I am not sure why. I dedided to fix my stuck odometer and I did that last night but when I put the cluster back in, my fuel gauge wasn't working again. This time it stuck on empty and I can't figure it out. I am getting constant 12v at the left post on the fuel gauge and the center one bounces around when reading it with my multimeter but is reading 7V and the right post is reading 40 ohms which should be a bit less than 1/2 full. Any thoughts? Do you think I should run a new wire from the fuel sending unit directly to the post on back of the fuel gauge and then run a new ground wire to the tab on the front of the fuel gauge? Thanks!
Thanks for the great post. I have a 75 FJ40 and my fuel gauge was previously always pegged on full. I read through these posts which helped me tremendously. Last week, I ended up pulling the fuel sending unit and testing it and it reads 12 full and 120 empty. I was getting the same reading at the connection at the cluster. I ended up pulling the cluster, pulled the fuel gauge and did the multimeter tests you listed on page 3 and came up with what you said they should be: Left to right: 25 ohm, Top to right: 25 ohm, Left to bottom folded lip (ground): 113 ohm, Right to bottom folded lip: 138 ohm
I ended up reassembling everything and the fuel gauge started working, although I am not sure why. I dedided to fix my stuck odometer and I did that last night but when I put the cluster back in, my fuel gauge wasn't working again. This time it stuck on empty and I can't figure it out. I am getting constant 12v at the left post on the fuel gauge and the center one bounces around when reading it with my multimeter but is reading 7V and the right post is reading 40 ohms which should be a bit less than 1/2 full. Any thoughts? Do you think I should run a new wire from the fuel sending unit directly to the post on back of the fuel gauge and then run a new ground wire to the tab on the front of the fuel gauge? Thanks!
Well I saw a previous post where the button can get pushed too far down and prevents the fuel gauge from moving. I got home and checked that and I had that issue. However, now the gauge goes to full again even though I am getting a reading of 42 ohms from the sending unit. Do you know why the fuel gauge would go to full every time? Thanks.
I ended up pulling the fuel gauge from the cluster and tested it by running 12v, a ground (to the little tab on the backside) and the fuel sending unit wire directly to it and still got bad readings. I purchased a replacement Orem fuel gauge from eBay and that one works so I had some sort of issue with the fuel gauge.
I bought a 60180 and performed the Light Shield Modification & ALL Yellow Stencil work . I went in from the back side as to NOT pry off the front cover
I have a 12/1978 build date FJ40 built for the USA market. For the last several months the fuel gauge will only read 1/2 full. It's worked perfectly the several years I've had the trunk until now. I have the Toyota Chassis and Body manual and followed the following steps in section 12-26. (FSM images already posted early in this thread)
Fuel gauge:
1. 3W bulb test - bulb turns on w/ ignition and after a few seconds starts to flash. BUT - I do not notice the gauge pointer "deflecting". Needle is at half a tank. How much should the needle deflect and should it go to full???
2. I have 12V at terminal A. At terminal B the voltage bounces between 2V and 7V....mostly. Occasionally it will hit 10V????
3. Resistance between B and C is 15 ohms - not 25.
Fuel Sender
F - 15 ohms
1/2 - 45 ohms
E - 125 ohms
Clearly the fuel sender is good. It seems to me the gauge itself is bad and I should buy a new one (83310-60013). BUT - before I do - is it a big deal that my voltage would spike to 10V? Don't want to buy a new gauge if the voltage regulator is actually the issue.
Thanks!
EDIT - Forgot to mention I also checked/cleaned the fuse and fuse box slots, the connections at the sender, the terminals on the cluster, and even removed the gauge and made sure the back grounding tab was clean and making good contact. No difference.
Fuel gauge:
1. 3W bulb test - bulb turns on w/ ignition and after a few seconds starts to flash. BUT - I do not notice the gauge pointer "deflecting". Needle is at half a tank. How much should the needle deflect and should it go to full???
2. I have 12V at terminal A. At terminal B the voltage bounces between 2V and 7V....mostly. Occasionally it will hit 10V????
3. Resistance between B and C is 15 ohms - not 25.
Fuel Sender
F - 15 ohms
1/2 - 45 ohms
E - 125 ohms
Clearly the fuel sender is good. It seems to me the gauge itself is bad and I should buy a new one (83310-60013). BUT - before I do - is it a big deal that my voltage would spike to 10V? Don't want to buy a new gauge if the voltage regulator is actually the issue.
Thanks!
EDIT - Forgot to mention I also checked/cleaned the fuse and fuse box slots, the connections at the sender, the terminals on the cluster, and even removed the gauge and made sure the back grounding tab was clean and making good contact. No difference.
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since u gave a 12/78 u have a 1 wire fuel sender , I would ADD a ring terminal and ground wire to one of the sender Phillips heads machine screws on the sender flange , if u have a existing ground wire on a ring terminal all ready verify its a Good ground
this just might be your problem
since u gave a 12/78 u have a 1 wire fuel sender , I would ADD a ring terminal and ground wire to one of the sender Phillips heads machine screws on the sender flange , if u have a existing ground wire on a ring terminal all ready verify its a Good ground
this just might be your problem
Thanks - I'll try that also but when I did the bulb test I used an alligator clip to a seat bolt vs. the sender's ground. Simple to try regardless.
Reason being in 1/79 toyota changed the sender to a 2 wire set up adding a dedicated ground wire to it , meaning they had problems with a No-Ground situation ..........
Hi all from Australia,
Hey Rudi, I worked in many electrical fields in my life, retired now, I cheer aloud each time I read your posts, always correct technical information and on target.
I just purchased a brand new cluster on eBay from Saudi Arabia, 5 digit odometer, reasonable price.
Now connected to fuel sender in my tank, 130 litter capacity, with 20 litres in sender reading 66ohms, yeah ok ish, gauge reads empty! It has moved from the rest position by about a needle width. Added another 20 litres, 55 ohms, gauge reads about 1/4 !
I will get to the bottom of it, possible gauge is calibrated for another sender or even the voltage regulator is out of specs. The temp display seems low also. The hj45 tray back( called a “ute” here) is not registered for the road yet also it’s a build with a different engine. 14BT.
JOHN
Hey Rudi, I worked in many electrical fields in my life, retired now, I cheer aloud each time I read your posts, always correct technical information and on target.
I just purchased a brand new cluster on eBay from Saudi Arabia, 5 digit odometer, reasonable price.
Now connected to fuel sender in my tank, 130 litter capacity, with 20 litres in sender reading 66ohms, yeah ok ish, gauge reads empty! It has moved from the rest position by about a needle width. Added another 20 litres, 55 ohms, gauge reads about 1/4 !
I will get to the bottom of it, possible gauge is calibrated for another sender or even the voltage regulator is out of specs. The temp display seems low also. The hj45 tray back( called a “ute” here) is not registered for the road yet also it’s a build with a different engine. 14BT.
JOHN
No change w/ the extra ground.
So I probably need a new gauge but I'm still wondering if the VR reading as high as 10V sporadically is an issue.
Does anyone know what role too high of a voltage would do to the gauge reading?
So I probably need a new gauge but I'm still wondering if the VR reading as high as 10V sporadically is an issue.
Does anyone know what role too high of a voltage would do to the gauge reading?
Does anyone know where I can source a Gauge Decal file so i can print them?
they will be in tomorrow real nice guy shipped them the very next day after i ordered
This on /off pulse gives the 7 volt discussed, that is 14v (nominal) on /off at a 50% duty cycle giving the AVERAGE of 7 volts.
I took the challenge and installed the electronic voltage regulator as discussed earlier in this post.
Now I have a steady 8 volts ( only 7808 voltage regulator available, 78 is the series and the 08 indicates the voltage output ) wow both displays steady and indicating what I feel to be correct values.
See photos re installation
Photos out of order, sorry.
First shows how I cut the thick wire from the mechanical voltage regulator to the centre connector of the fuel gauge, also the thin wire was unsoldered from the centre connector.
Second photo shows the original Toyota setup in the fuel gauge.
Last photo shows how I mounted the 7808 voltage regulator, a M3 hole was drilled and tapped, M3 screw attaches the regulator to the cluster without any insulation ( the mounting tab is at negative voltage, the top wire goes to 12v, the centre wire goes to negative( to make sure of a reliable negative connection) the bottom wire goes to the connection between fuel and temp gauges supplying the 8 volts.
It works,
Post if you want more details.
The white mess is a NON corrosive adhesive
Would this of helped out in any way ?
u have the New 83100-60180 correct
I spent the last 6 months working with a Customs Company & Reproduced the Original YAZAKI brand Black 12 pin Barrel Connector
i was limited to White in color
I have All the correct OEM color Coded tracer stripe wire colors , for the various years spans NON-usa & Usa spec.
The terminals are Solid Spring Brass just like OEM
