Allison HT740 trans speed sensor issue

[JT4SC]

I have attached a couple pictures showing wiring coming from the tranny, then teeing off with one set of wires going to electrical box near the tranny dipstick and the other wires going over the tranny to the other side, where there are 2 connectors.

Let me know if you have any questions about the pictures, thanks again for everyone's help!!

[azdieselman]

Looks like neutral safety and back-up lights.

[bevans6]

On my tranny, admittedly a MT647, those are the neutral switch (bottom picture, beside the shifter cable) and the reverse switch.  So I agree with AZD.  If that's all the wires there are, there doesn't seem to be a speed sensor in the transmission.  I like threads like this, I learn a lot from the conversation.

[Scott & Heather]

I know this thread is older, but since I'm chasing down a speed sensor issue on my 102C3, I want to throw in a data point. No one has mentioned the HT748. That's the electronic version of the 740 of I'm not mistaken and it's the trans that I indeed have in my 1992 102C3. Atec touchpad and computer. So maybe the original poster had a 748. Not sure but they indeed did appear to put 748 trans into 102C3's.