Governor Pressure Sensor Voltage (P1762, P1764)
 

Hi All,

I changed the tranny fluid and filter in my wife's 1997 Grand Cherokee
a few weeks ago. While I had the pan off, I decided to adjust the
bands. Everything was going fine until today, when the check engine
light came on. My OBD2 code reader gives me the codes p1762 and P1764,
which are "Governor Pressure Sensor offset improper voltage" and
"Governor Pressure Sensor voltage too low" respectively. There is also
noticeably lower than usual torque to the wheels from a dead start in
first gear, which I assume is related...it's nowhere near as quick to
get going as it usually is.

I know it's possible that it's a crapped-out governor solenoid, but
since it happened so soon after I messed with the bands, I have a
feeling that something I did caused this to occur. I did have a hard
time getting the forward band adjusted correctly, because it was hard
to get to the adjuster bolt, so it's possible that it's either not
adjusted right, or it was adjusted right, but I didn't get the locknut
tightened enough, so it's gone out of adjustment. Is it possible that
the forward band is the problem? Or do I likely have to replace the
Governor Pressure Sensor? Is there any way to check the voltage of the
Governor Pressure Sensor with a multimeter?

Thanks for any help,
Tom

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

After doing a little more reading on the subject, I'm starting to
think that it probably has nothing to do with the bands, and more to
do with the fresh new tranny fluid helping to work sludge free that
has since clogged up the governor pressure sensor. I'd be very
interested to know what any of you might think...

Thanks,
Tom

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

After doing a little more reading on the subject, I'm starting to
think that it probably has nothing to do with the bands, and more to
do with the fresh new tranny fluid helping to work sludge free that
has since clogged up the governor pressure sensor. I'd be very
interested to know what any of you might think...

Thanks,
Tom

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

After doing a little more reading on the subject, I'm starting to
think that it probably has nothing to do with the bands, and more to
do with the fresh new tranny fluid helping to work sludge free that
has since clogged up the governor pressure sensor. I'd be very
interested to know what any of you might think...

Thanks,
Tom

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

After doing a little more reading on the subject, I'm starting to
think that it probably has nothing to do with the bands, and more to
do with the fresh new tranny fluid helping to work sludge free that
has since clogged up the governor pressure sensor. I'd be very
interested to know what any of you might think...

Thanks,
Tom

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

googlegroups wrote:
> After doing a little more reading on the subject, I'm starting to
> think that it probably has nothing to do with the bands, and more to
> do with the fresh new tranny fluid helping to work sludge free that
> has since clogged up the governor pressure sensor. I'd be very
> interested to know what any of you might think...

If that was the first transmission fluid change then you could be
correct. First check the connections to make sure you didn't knock
them loose.

You can use a suction pump to pull fluid out the dipstick. That will
give you an idea of how much gunk came free.

Did you get the filter and pickup back in properly? That can cause
low pressure because of starvation.

Never did bands myself, it was easier to just let the dealership
screw me out of a few bucks than take time off work. :] So I can't
answer that question.

The only other question is the fluid type. Mixing some types will
cause serious problems. Usually you notice this because the fluid
turns to brown sludge. ATF +3 and Dexron/Mercon II are supposedly
compatible, but ATF T and F are from what I read, not compatible
with older fluids. It's mineral oil vs silicone. The 97 should still
be using ATF +3, but check the service manual to be sure.


--
DougW

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

googlegroups wrote:
> After doing a little more reading on the subject, I'm starting to
> think that it probably has nothing to do with the bands, and more to
> do with the fresh new tranny fluid helping to work sludge free that
> has since clogged up the governor pressure sensor. I'd be very
> interested to know what any of you might think...

If that was the first transmission fluid change then you could be
correct. First check the connections to make sure you didn't knock
them loose.

You can use a suction pump to pull fluid out the dipstick. That will
give you an idea of how much gunk came free.

Did you get the filter and pickup back in properly? That can cause
low pressure because of starvation.

Never did bands myself, it was easier to just let the dealership
screw me out of a few bucks than take time off work. :] So I can't
answer that question.

The only other question is the fluid type. Mixing some types will
cause serious problems. Usually you notice this because the fluid
turns to brown sludge. ATF +3 and Dexron/Mercon II are supposedly
compatible, but ATF T and F are from what I read, not compatible
with older fluids. It's mineral oil vs silicone. The 97 should still
be using ATF +3, but check the service manual to be sure.


--
DougW

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

googlegroups wrote:
> After doing a little more reading on the subject, I'm starting to
> think that it probably has nothing to do with the bands, and more to
> do with the fresh new tranny fluid helping to work sludge free that
> has since clogged up the governor pressure sensor. I'd be very
> interested to know what any of you might think...

If that was the first transmission fluid change then you could be
correct. First check the connections to make sure you didn't knock
them loose.

You can use a suction pump to pull fluid out the dipstick. That will
give you an idea of how much gunk came free.

Did you get the filter and pickup back in properly? That can cause
low pressure because of starvation.

Never did bands myself, it was easier to just let the dealership
screw me out of a few bucks than take time off work. :] So I can't
answer that question.

The only other question is the fluid type. Mixing some types will
cause serious problems. Usually you notice this because the fluid
turns to brown sludge. ATF +3 and Dexron/Mercon II are supposedly
compatible, but ATF T and F are from what I read, not compatible
with older fluids. It's mineral oil vs silicone. The 97 should still
be using ATF +3, but check the service manual to be sure.


--
DougW

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

googlegroups wrote:
> After doing a little more reading on the subject, I'm starting to
> think that it probably has nothing to do with the bands, and more to
> do with the fresh new tranny fluid helping to work sludge free that
> has since clogged up the governor pressure sensor. I'd be very
> interested to know what any of you might think...

If that was the first transmission fluid change then you could be
correct. First check the connections to make sure you didn't knock
them loose.

You can use a suction pump to pull fluid out the dipstick. That will
give you an idea of how much gunk came free.

Did you get the filter and pickup back in properly? That can cause
low pressure because of starvation.

Never did bands myself, it was easier to just let the dealership
screw me out of a few bucks than take time off work. :] So I can't
answer that question.

The only other question is the fluid type. Mixing some types will
cause serious problems. Usually you notice this because the fluid
turns to brown sludge. ATF +3 and Dexron/Mercon II are supposedly
compatible, but ATF T and F are from what I read, not compatible
with older fluids. It's mineral oil vs silicone. The 97 should still
be using ATF +3, but check the service manual to be sure.


--
DougW

Re: Governor Pressure Sensor Voltage (P1762, P1764)
 

Thanks for the reply, Doug. No, it wasn't the first fluid change, but
it has been about 4 years since I did it last, and the car does have a
little over 180,000 miles on it...


> You can use a suction pump to pull fluid out the dipstick. That will
> give you an idea of how much gunk came free.


Okay, I'll give that a try.


> Did you get the filter and pickup back in properly?


I think so. They're definitely in there, and I'm reasonably certain
that I did it properly.


> The 97 should still
> be using ATF +3, but check the service manual to be sure.


It calls for ATF+3, but I couldn't find any, so I used a synthetic ATF
+4, which is supposedly compatible with ATF+3...I could see where it
might be the problem, though...


Thanks,
Tom