yes I know another friggin question about these friggin aweful autos however this will get you all thinking. I have one of these boxes in a 67 mustang. I'm having (if you hadn't guessed) problems with the auto going into LHM. It will be fine for the first few minutes of driving then bugger LHM. I was thinking if not having any ABS sensors sould cause this? I have replaced nearly everything else.

Also would having the actual speedo instrument inself out of the cluster cause problems. I use the instrument cluster so the correct signal goes to the ecu and TCM. I have just removed the physical speedo as a run an aftermarket VDO one?

Any thoughts?

If the box isn't receiving a speedo signal, or gets an intermittent one it will go into limp home mode.
AFAIK the TCM, in my car it's combined with the ECU though, needs the speedo signal to select shift points electronically via the speedo in the cluster.
I'm no expert in this but you may have to refit the speedo somehow, [maybe hide it?] unless one of our electronics gurus like 'Snap0694' or 'coupe66' can think of a way around the problem.
Cheers,
Paul

Paul has it pretty much correct, although I'm not a guru by any means.

It certainly looks like a SS input issue.

I'd suggest pulling the fault codes from the TCM, and see what comes up - bear in mind they are two digit codes.

Try installing the factory speedo, and see if anything changes - theoretically it shouldn't, but wouldn't hurt.
ABS shouldn't influence LHM.

well well, i found an article from the us that says without the physical speedo the gearbox will go into lhm, purely as a means to stop odometer fraud. I put it in and the problem isn't that bad, although still happens occasionally.

I noticed today the auto slipped so I topped it up with fluid and it fixed that problem however lhm still creeps in occasionally.

I have fitted a vdo speedo to replace the cable driven one. The only place i can hook the speedo up to is the input into the cluster or straight from the vss. I figure that it must be ok because the car runs fine for a while. I took it for a sping today and it changes up gears nicem kickdown works. I went to do a full throttle start and it revved up for a little bit in first then went into lhm. hmm switched off, tried it again same thing. Gentle starts are not a problem. I'm going to fit a cooler this weekend but it can drive around all day as long as it is treated gently. figured overheating may be a problem.

i tried to get the codes out today and i can't anymore!! now corrcet me pin to to led light and pin 20 to ground? I have replaced the inhibitor switch and changed to a known to be working vss.

if it isn't an overheating problem i think i'm going to go manual.

oh yeah that is the other thing, i can't maually shift gears. If i put it in first it still changes through the gears..which makes me think that it is still the inhibitor switch somehow..or the wiring. in any case the seats etc are coming out and i'm going to re check the wiring *sigh*

EDIT:
Just went to move the car intot he garage and noticed when I put the shifter into drive the speedo needle jumps up and down.

I think a manual box is looking more likely.