Where does this wire go?

[mikemac3]

Trying to diagnose the cause of my tachometer and engine temp gauges not reading (instead they are flopping all over). Found this wire that looks like it either needs a cap or should be connected to something. If you know, could you direct me to what it connects to or where I can buy its cap.

I'm driving a new to me 2000 Allegro Bus with 350 HP cummins on a frieghtliner chassis. The wire is on the left side of the Allison transmission right near the data plate.


Hoping this mystery will solve all of my problems.

Thanks for the help!

Mike

[BFlinn181]

If there's no matching wire and plug within reach of that plug, I'm not sure it will solve your issues. The tach and engine temperature signals probably come from your ECU, so a dirty connection there could be the culprit. In addition, a bad ground under the dash could also cause jumping gauges.

I'd start checking all connections at the engine and work forward, unclipping, spraying clean the contacts, and reconnecting as you go.

[Skip426]

Mike ; have you checked back on your other post ? Wiring is for a mid trans sensor that Allison no longer uses. Should be cleaned and covered with a waterproof material.

While your in the transmission area, look for a 7 foot coil of wire on top , with a data connector on the end, grey with a cap, Freightliner supplied it with the chassis harness and Newmar was to locate it. Didn't get done , I ran mine up the trans dip stick tube and hung it inside the engine rear cover .