Pulldown resistors for TPS MAP

[Bruce Plecan]

-----Original Message-----
From: goflo at pacbell.net <goflo at pacbell.net>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Monday, August 03, 1998 3:59 PM
Subject: Re: Pulldown resistors for TPS MAP


>This is the most likely, and will give 0 to nearly 5V adj
>
>        5V   ______
>                   |
>                   /  5K pot, linear taper 
>                   \
>                   /<------ Variable voltage to ECU input
>                   \
>                   /
>                   |                   |
>                   |
>                 Ground


This is what I have..
>
>                          /*  less likely  */
>
>5V pull-down  _____
>voltage from       |                   
>ECU                |
>                   /  5K linear taper pot
>                   \
>                   /<---------/\/\/\-------- Ground
>                   \            1K 
>                   /            
>                   |
>                   |
>               No connection

Where is the ecm connected?.  Or in this version just thru the 5K.

The Coolant temp sensor, and Intake Air Temp have two terminal
connectors, and the TPS, MAP have three terminal.  I verified that
there is 5v to them, a ground, and the sensor signal to ecm (unk)
Cheers
Bruce
>                 
>This will give approx 1V to 5V adj. If you need less than 1V
>( say .9V ) use a smaller current limiting resistor, but at 
>least 500 ohms or so. This resistor prevents shorting the 5V 
>input to ground at the high end of the pots travel ... If the 
>ECU uses this scheme the current is probably internally limited
>but we dont need to find out the hard way that it is'nt. It is
>Monday, after all.
>
>If this doesnt make sense describe the connections as fully as 
>possible and we'll beat on it some more.
>
>Regards, Jack
>