Re: [DML] Automatic transmission

["Walter" <Whalt@xxxx>]

Arne,

I found it! But not in the archives. I found it using a search utility on
my own hard drive. I suppose it won't hurt to have the whole thing re-posed
to the archives again -- it is very valuable advice in my opinion.

Also about starting in second gear. Yep, I stand corrected. I was
remembering what my old (bad) GC did with a blown cap. With both solenoids
off, you are in 3rd gear.

Here's the old post:

-----Original Message-----
From: Peter Lucas <lucas@xxxx>
To: dmcnews@xxxxxxxxxxxxxxx <dmcnews@xxxxxxxxxxxxxxx>
Date: Saturday, February 24, 2001 5:33 PM
Subject: Re: [DML] Auto trans gov. problems...

<snip>
>In diagnosing this kind of problem, it is essential to first
>determine whether the governor is at fault or whether you have a
>mechanical problem. Fortunately this is easy to do. You need to build
>yourself a little test rig that lets you see (while you drive) what
>the governor is telling the transmission. This has been covered in
>the list in the past (check the archives), but here's the general
>idea:
>
>1) Find the round black terminal block where the computer governor
>connects to the solenoid wires. It is in the engine compartment on
>the left firewall. Looks like some kind of diagnostic connector, but
>is really just a set of terminals. There are three wires going
>through this connector: One each for the two shift solenoids and a
>common. The center terminal is common. There are also two unused
>terminals. If we number the five terminals clockwise from 1 to 5,
>what we want to monitor is the potential between terminals 2 and 3
>and between 3 and 4. If I remember correctly, the common (terminal
>3) signal is +12V, and terminals 2 and 4 get pulled to ground by the
>governor to activate the respective solenoids. In any event, this can
>readily be determined with a test light or voltmeter. When the car
>is in neutral or low gear, you should read a 12V potential between 2
>and 3 and also between 4 and 3. The trick is to be able to watch how
>this changes when the transmission is in action.
>
>2) To accomplish this, run a 3-wire cable from this connector into
>the passenger compartment (4-wire telephone cable from Radio Shack is
>good for this). Connect the three wires to terminals 2, 3, and 4. Run
>the wire up your steering column so it comes out between the dash and
>the column.
>
>3) Obtain 2 LEDs (Radio Shack again) one red and one green. You also
>need two 1500 ohm (brown green red stripes) resistors. Connect a
>resistor in series with the other end of the wires coming from
>terminals 2 and 4. Connect the other side of the resistors to the
>negative (unmarked) sides of the LEDs. Connect the positive (marked)
>sides of the LEDs (I'm doing this from memory--hope I don't have it
>all backwards) together and also to the wire coming from the center
>(#3) terminal. You can impress your friends by neatly packaging this
>precision instrument inside a 35mm film can.
>
>4) Loosen your steering wheel adjustment clamp (you *do* know you
>have one, right?) and let the wheel drop. Position the film can
>between the steering column and the dash positioned so that you can
>see the LEDs while driving and slowly raise the wheel so that the can
>is firmly captured. Tighten the wheel in place.
>
>5) Turn on the key. Both LEDs should now be shining cheerfully
>(assuming your governor is functioning semi-correctly).
>
>6) Go for a ride. If he governor is operating correctly, the lights
>should go out one as a time, as the car shifts into second and third
>gear, respectively. In high gear, both lights should be off. When
>the vehicle downshifts, the lights should come back on in turn. It
>should now be an easy matter to decide whether your particular
>aberrant transmission behavior is due to bad advice from the governor
>or mechanical problems in the transmission itself.
>
>If you are not comfortable dealing with such highly sophisticated
>digital circuitry, please get some advice from somebody who is. I may
>have gotten all this wrong and of course accept no responsibility for
>damage to you or your vehicle.
>
>Hope this helps,
>
>Pete Lucas
>VIN #06703