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General Boards => Technical Support => Topic started by: Roland DuBree on March 07, 2021, 07:10:59 PM

Title: 37' 2001 beaver contessa Transmission temp. sensors
Post by: Roland DuBree on March 07, 2021, 07:10:59 PM

where are transmission Temp. sensors located on a 3129 cat system in a 37' Contessa?  Temp to computer scan works fine but dash gage always reads zero!  Are sensors interchangeable? How to test to see if sensor bad or dash gauge bad?

Title: Re: 37' 2001 beaver contessa Transmission temp. sensors
Post by: Steve Huber on March 07, 2021, 07:49:17 PM

See pg 13 of the 2002-2003 Patriot wiring diagrams in Coach assist for the gauge wiring. It has 3 connections. The top wire is ground. One of the 2 bottom wires is ignition power (12v when key on). The remaining wire is from the sensor. It will provide a resistance to ground depending on the temperature being sensed. If you ground it thru a resistor the gauge should react if it is working.
Steve

Title: Re: 37' 2001 beaver contessa Transmission temp. sensors
Post by: Roland DuBree on March 07, 2021, 10:18:15 PM

How do I get to the diagram? When I log on to Forum, general boards, private BAC members only board, I get no link that says Coach Assist: Owners and Equipment manuals?

Title: Re: 37' 2001 beaver contessa Transmission temp. sensors
Post by: Steve Huber on March 07, 2021, 10:30:24 PM

Coach Assist is on the BAC Website https://www.beaveramb.org/
Log in and select the Technical tab in the blue banner across the upper section of the home page. It will bring up the technical sections including Coach Assist.
Steve

Title: Re: 37' 2001 beaver contessa Transmission temp. sensors
Post by: Roland DuBree on March 16, 2021, 10:30:15 PM

Assuming the gauge is good, although I have not tried the test you suggest, where would the sensors be located?    I assume there are 2 some place - one for the dash gauge and one for the Silver Leaf scanner system that works fine.

Title: Re: 37' 2001 beaver contessa Transmission temp. sensors
Post by: Eric Maclean Co-Admin on March 17, 2021, 01:35:14 AM

Roland
You are correct there are two sensors your silver leaf is actually reading from the transmission  control module (TCU) electronic data .The sensor it is reading is located inside the Allison automatic transmission and is part of the wiring harness inside the transmission.
The dash gage has its own sending unit and it is usually located in a tee on one of the transmission cooler hydraulic lines close to the transmission cooler with a single wire connected heading to the dash gage.
Hope this helps
Eric