Builds 1978 US Market FJ40 Factory Restoration

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Green Bean said:
On the parking brake, I encountered a similar issue and upon disassembly discovered that the little tiny retaining clip securing the parking brake cable to the backing plate had become dislodged.
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It feels like that may be the case, ugh. Will know more when I can dig into it this weekend. I do, however, wish there was a better way to adjust/tighten the 17mm's at the firewall, literally a jungle and difficult angle.
 
Safety inspection! Thank goodness the parking brake isn’t on the safety list. I'll be working on that and the fuel gauge next. Might take me a week or two as this weekend is spoken for.

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Its almost too quiet, if anything. Maybe that will change with miles, but I was hoping for a wee-bit more truck sound. I can barely hear the thing! Which, my wife approves of 1. zero exhaust smell and 2. we can hear each other talk.

I'll see if I can get a video posted of driving around, I've taken a few. Stand-by.
 
Diagnosing the inoperable fuel gauge. With a new fuel level sending unit and a rebuilt gauge cluster, I searched for tips on how to diagnose and found an old post by Poser.

Test one: Ground. Not knowing anything beyond very novice skills in using a multi-meter, I set it to "ohms". I put the black feed of the multi-meter on the fuel sending unit screw that has the ground wire attached and the red feed to the body (seat bolt) and the meter went from 0.L to 0.000001. If I tested ground anywhere else, the meter remains "0.L". So, without in-depth Chinese volt-meter knowledge, I assume we have a good ground.

Test two: Yellow/Red feed wire from the male prong on the sending unit to the back of the cluster. I removed the plug from the sending unit and put the red feed line in the end of the plug. Then, I removed the gauge cluster and put the black feed in the yellow/red wire hole, again, meter went from 0.L to 0.000003 or some number. If I tried anywhere else, again, the meter doesn't read. So, I am assuming we have a solid wire from point A to B.

I guess this means an issue with the Fuel gauge itself? The cluster has a new circuit board and the pins /wires are all new.

This is probably my next move:
 
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Have you tried grounding the sender wire at the tank? When grounded the dash gauge should react with key on. Ground just enuff for some movement. If it doesn't then its probably at the gauge. You might double check the senders resistance levels too. There should be a range of resistance thru the arms sweep. The FSM should give you ohm values for testing.
 
Pulled the cluster, took out the gauge and ensured it passed visual inspection as well as the grounding tab making good contact with the body of the cluster.

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All visual inspections pass - pulled the gauge itself and applied 12 volts to it per the above youtube. It passes and began to "raise" as if fuel in the tank. So, it appears the gauge, itself, is functioning.

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I re-tested the ground and feed wire at the fuel sending unit. Both good. So, now I've (I think) narrowed it down to either a stuck sending unit or a bad sending unit. It is a brand new Toyota part, so I'd be surprised if its "bad". But, will have to remove the seat and pull the sending unit to evaluate. Grrr.
 
Well, burned my lunch hour working on this. I tested the sending unit - its good.

So then I put everything back together....and the turn signal lights were stuck on. However, the turn signals and hazards work? Then...I noticed the fuel gauge going up!! Sweet, the fuel gauge works, but why the turn signal lights stuck on? So, I reached up behind the cluster and ensured the cluster plug was snug and when I pushed it, the lights went out, as they should, but the fuel gauge stopped working again.

Appears there is a short/wiring issue in that black circular plug or something. Ridiculous!

Anyone ever get a fault like this? Not sure how that thing (which is keyed) is somehow causing a short, or behavior like this. Throwing in the towel for today.
 
Inspect the round barrel connector. Those small brass terminals inside get loose and frayed over the years. Post up a photo of the wires going into the connector. If you need a barrel connector and terminals just let me know. I’ve got tons of them.
 
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Starting with fuel sender moving counter clockwise:

YR —fuel sending
LR— 12v key
X
YB — oil pressure
WB — ground
RB — instrument light
GB— left turn indicator
X
GY— right turn indicator
LW <—Not in the diagram, maybe emissions?
RY— high beam indicator
YG?— temperature
 
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Did you test the cluster by itself? Supply 12v and ground at the prongs where the round plug would attach and see if the circuit board works as designed? That way you can rule out the cluster entirely.

If you've confirmed its not the cluster, then yes it is time for a new terminal housing and make sure the wires aren't frayed/damaged when installing new terminal housing.
 
While I have no idea why the "short" occurred - I can say this... I just disassembled the pins from the barrel connector and what I thought was a waxed up OEM connection paste is.....ready for this? YAY SILICONE! Scroll up to those photos I posted before. That is silicone.

As I was removing the plugs, the previous owner in his infinite wisdom, thought it would be a good idea to silicone them all into place. Silicone is in each of the slots and all over the connectors.

There's no way this is a Toyota thing, right? I've never encountered anything like this on any other 40, and several have passed through my ownership over the years.

@Ackcruisers - let me know if I can purchase a barrel connector from you. Since we're also in the same neck of the woods, it should arrive fairly quickly.

I know it's a hassle, sorry. Will make it worth your time. Digging all of this silicone out of here will just damage the connector.

Thank you!
 
dmaddox said:
While I have no idea why the "short" occurred - I can say this... I just disassembled the pins from the barrel connector and what I thought was a waxed up OEM connection paste is.....ready for this? YAY SILICONE! Scroll up to those photos I posted before. That is silicone.

As I was removing the plugs, the previous owner in his infinite wisdom, thought it would be a good idea to silicone them all into place. Silicone is in each of the slots and all over the connectors.

There's no way this is a Toyota thing, right? I've never encountered anything like this on any other 40, and several have passed through my ownership over the years.

@Ackcruisers - let me know if I can purchase a barrel connector from you. Since we're also in the same neck of the woods, it should arrive fairly quickly.

I know it's a hassle, sorry. Will make it worth your time. Digging all of this silicone out of here will just damage the connector.

Thank you!
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Silicone is not something I’ve ever seen…maybe dielectric grease but never silicone. PM me your address and I’ll drop one in mail tomorrow morning.
 
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