Power seat problem

The driver's side power seat on my 1995 Ford Crown Vic won't go
forward. It will go backward, but not forward. There is no obstruction
under the seat. Is this just a motor problem?

On 19 Oct 2005 06:55:39 -0700, "lou" > wrote:

>The driver's side power seat on my 1995 Ford Crown Vic won't go
>forward. It will go backward, but not forward. There is no obstruction
>under the seat. Is this just a motor problem?

Okay, you know this is a DC motor, and you get it to spin in one
direction by having +/-, and spinning in the opposite direction by
reversing polarity to -/+.

Whatever is reversing the polarity ( a double pole double throw switch
addressing a diode bank ) is most likely responsible for this problem.
My guess is you will find a defective diode on a small PCB that the
seat switch attaches to.

Lg

Lawrence Glickman > writes in article > dated Wed, 19 Oct 2005 09:09:22 -0500:
>On 19 Oct 2005 06:55:39 -0700, "lou" > wrote:
>
>>The driver's side power seat on my 1995 Ford Crown Vic won't go
>>forward. It will go backward, but not forward. There is no obstruction
>>under the seat. Is this just a motor problem?
>
>Okay, you know this is a DC motor, and you get it to spin in one
>direction by having +/-, and spinning in the opposite direction by
>reversing polarity to -/+.

I'm with you so far. It's probably the switch.

>Whatever is reversing the polarity ( a double pole double throw switch
>addressing a diode bank ) is most likely responsible for this problem.
>My guess is you will find a defective diode on a small PCB that the
>seat switch attaches to.

I don't understand why you'd need a diode if you had a DPDT switch reversing
the polarity for you.

-- spud_demon -at- thundermaker.net
The above may not (yet) represent the opinions of my employer.

On Wed, 19 Oct 2005 20:36:00 +0000 (UTC), (Spud
Demon) wrote:

>Lawrence Glickman > writes in article > dated Wed, 19 Oct 2005 09:09:22 -0500:
>>On 19 Oct 2005 06:55:39 -0700, "lou" > wrote:
>>
>>>The driver's side power seat on my 1995 Ford Crown Vic won't go
>>>forward. It will go backward, but not forward. There is no obstruction
>>>under the seat. Is this just a motor problem?
>>
>>Okay, you know this is a DC motor, and you get it to spin in one
>>direction by having +/-, and spinning in the opposite direction by
>>reversing polarity to -/+.
>
>I'm with you so far. It's probably the switch.
>
>>Whatever is reversing the polarity ( a double pole double throw switch
>>addressing a diode bank ) is most likely responsible for this problem.
>>My guess is you will find a defective diode on a small PCB that the
>>seat switch attaches to.
>
>I don't understand why you'd need a diode if you had a DPDT switch reversing
>the polarity for you.

I don't know what is in the control unit. I am just guessing.

The electrical systems in today's automobiles are NIGHTMARES with your
eyes wide open. If you can fix this problem yourself, pat yourself on
the back.

Some manufacurers do crazy things with design, to save a penny here,
and save a penny there. You can almost be assured they are taking the
cheapest way out when it comes to specifications, even when they build
for the military.

Lg


>
>-- spud_demon -at- thundermaker.net
>The above may not (yet) represent the opinions of my employer.