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TR4/4A Voltage stabilizer wiring question

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JimTR4

JimTR4

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Hi all - I have a 64 TR4 converted to negative ground/earth.
I am attempting to isolate the feeds to the heater fan motor and the wiper motor wiring so I can fuse them separately.
At the voltage stabilizer, I see 3 green wires that effectively are all connected together and a single green/black that is on a separate blade terminal (looks to be the gauge feed).
My question is this, one of the green wires comes from the fuse block and so supplies power to the stabilizer and other circuits I mention, can i take the other 2 greens off the stabilizer completely and feed them from the fuse block with their own fuses WITHOUT causing any issues with the stabilizer?
I'm hoping I'm making sense here - there would still be the original feed from the fuse block to the stabilizer but I THINK I end up with 2 separated feeds for wipers/heater. I've attached before and after pics to help (maybe!).
Thanks.
 

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I follow you. Your second picture is electrically the same as the first. To fuse the heater and wiper motors separately (which I think is a good idea), you should run a wire from the source side of the fuse block (A3) through a fuse and then to the switch and motor. Do this for both motors.
 
Yeah I was trying not to leave redundant wiring in the loom. I think if I do it my way I at least continue to use existing wiring and not have to thread 2 new wires through behind the dash. I'm having problems determining which green (at the stabilizer) is the feed from the fuse block. I get continuity from all three. 2 are connected to the same blade terminal and 1 is separate. I had assumed that was the feed but testing for continuity back to the fuse from the paired 2 and the single green shows they are all connected. I'm a bit confused...
 
Get a Tr6 fuse block and make a neat looking installation. This gives you more fuses & safety.
The wiper/heater motors do not care about the grounding change.
The modern stabilizers DO care and you must use the right one. Check that you have 9 volts to power the
gages and don't forget to refresh all the grounds on the chassis/body.
Mad dog
 
The fuel gage needs 9 volts on most Tr4's early cars did not . The early cars were more Tr3 ish.
Mad dog
 
To find the feed, disconnect both ungrounded wires at the stabilizer, turn on the power, and carefully measure the voltage at those wires. the feed will be hot, the other not.

As you've discovered, continuity checks can be tricky. Unless you isolate the part of the circuit you want to test, you can easily have other paths that test as continuous.
 
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