Mmm unfortunately I work for Isuzu and no one has any idea what’s wrong with this thing no ones had this issue with any of their trucks before and everyone I talk to about it is just backing away leaving me in the dark so I just had to try something to save it. I have a feeling that the it is holding both solenoids on at the same time to activate 1 solenoid takes only 5 amp but if it’s held it can draw up 22amps I don’t know what the internals of the TCM are rated for but that seems to be a lot for any poor pcb trace to handle
Thanks for the help though but if no one has any idea on how I can get this to work I don’t know what I can do
tcm to control SSR correctly
Re: tcm to control SSR correctly
I'd fuse the individual outputs to protect the TCM just in case...
That also may point you at the problem if you can get it to blow with regularity
That also may point you at the problem if you can get it to blow with regularity
According to chemistry, alcohol is a solution...
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Commodore VF Series II SSV Redline
Re: tcm to control SSR correctly
Now, this is a bit worrying. A short between the drive lines to the 1,3,5 and 2,4,R solenoids would of course cause them to energise simultaneously (but incorrectly) and it would also screw up any valid feedback current sensing.I have a feeling that the it is holding both solenoids on at the same time
I'd have a very good look at that wiring loom again!
Re: tcm to control SSR correctly
I’ve tried fusing them before and after the tcm problem is that the solenoids draw any where from 5-20amps at hold but the tcm is not able to handle a hold of 20amps so it’s just popping the fuses purely due to load. We had the harness out completely stripped it even checked every pin is in correct positions found a couple of issue wires repaired them but still getting the issue on top of it this fault is completely random sometimes it happens straight away other times it’s 2,3,4 or 5000km
Re: tcm to control SSR correctly
What about a thermal circuit breaker at what ever the TCM is rated at, that will give some time for the current to settle down in hold before it blows/opens the circuit?
I know that, that is not fixing the issue but it would prove that the fault is in the box, which based on what you've said I suspect.
I know that, that is not fixing the issue but it would prove that the fault is in the box, which based on what you've said I suspect.
According to chemistry, alcohol is a solution...
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- Posts: 27
- Joined: Mon Sep 09, 2019 9:59 pm
- cars: Commodore VR Series II SS
Commodore VF Series II SSV Redline
Re: tcm to control SSR correctly
With all the wiring checks you’ve done, I agree the box is most suspect. I’m curious to know whether, in all of those blown TCMs, was it always the one output driver that was blown? If it were always, say, the 1,3,5 solenoid driver, then that solenoid may have shorted coil turns or a short to its case.
Re: tcm to control SSR correctly
I could try that I suppose put a thermal unit in there. Yea every time it’s always the driver inside the tcm that blows out smokes it’s self and tries to unsolder itself from the board coupe of times it was the 2,4,R solenoid. We’ve put a coupe of new solenoids into it now thinking it was them and the brand new trans came with new solenoids on it as well