Hi,

When I bought the car, the speedo, odo and tripmeter were not working.
I thought this would be because of a faulty speedo sensor on the TH400 transmission, but soon found out that the sensor is brand new and no wires are damaged.

Have to sort that out with a multimeter, but that shouldn't be a problem.

another issue is, that the tripmeter can't be reset.
When i push the reset pin, nothing happens.
I opened up the speedo to see if there is anything mechanically wrong, but can't find anything out of order.

How does this tripmeter work?
Can it only be reset while it has power or while driving?
Can't drive the car at the moment because it has some body parts missing at the moment ;-)

Help would be very much appreciated... ;-)

 

Small help if any from electronically challenged me.


1. You have two somewhat inter related issues. No signal from the transducer. From an of tech "trick" you might get a bit of help[. In ancient days, cable speedo's were backed up by a drill. chuck in he cable. Fire up the drill in reverse and crank out the odometer!!!


So, can you concoct a mechanical connection from a drill driver to the transducer drive. Then does the speedo read anything?


Most of us do not have signal generators. should you be so fortunate, Hook one up down and under at the transducer output to the speedo. If it reads, the speedo and the harness to it sound.


Rough ready and perilous: Of the "don't do this at home" that some of us do and survive. Jack the car up. BEWARE of LSD, the mechanical kind, run in gear. The speedo should read.


2. Trip computers do go kerplunk. I have one in my car that works, sorta and another that is completely nuts. But, does it even light up. An indication of getting power. Not conclusive, though. does the clock work? Will it respond to a reset? It has two other inputs. Only one is distance. Only source, the transducer. But, fuel!!!
My diagnosis from afar is a Kerplunked trip computer... Fixable, only maybe.


3. If you really like one, get a known working one from David Boger.


Carl

 

With the electric speedometer the odometer and trip odometer use 'stepper motors' to operate. Now you know as much as I do .

Do you also have the trip computer above the radio? if so, does it register/calculate miles driven? If 'yes', then your transducer is working and the signal isn't reaching the speedometer, or the speedometer is faulty, or the speedometer is not grounded, or the speedometer lacks "key on" voltage.

If the trip computer is not recording miles driven then nothing much is proven because, as Carl says, they often go kerplunk !

Cheers
DD

 

Thanks for the answers guys!

My Cat doesn't have a trip computer, it has a nice ancient looking clock where the trip computer normally goes. Looks pretty original to me.

The speedo problems I can sort out, that will not be the problem:
Either the entire speedo is defective, or the transducer, cabling or the gear inside the tranny is stripped.

What really annoys me is that I can't reset the "day counter". The lower of the mechanical odo's in the speedometer. Can it only be reset while driving and/or while powered, or is it good old fashioned mechanical and should go to 0000 when the button is pushed in, regardless of the actual situation?

 

The reset on theses speedos are notoriously bad. I've just replaced the whole speedo with one that works. Most used ones don't When I rebuilt my 82, I put in a nos speedo. Reset works but the one in my 87 quit resettling.