Cirrus 1999 LXi Codes P0700, P0720, P0731

Hello,
I've got recently used Cirrus 1999 with 170K km on board. Drives very
good, and for the first 2000 km done by me it was without any problem,
but yesterday I start to learn what is this "limp mode" and how does ii
feels like Actually it was going in and out from Normal-Limp-Normal,
with speed showing 0 km/h in the time i was with 50-60km/h, and in the
same time FUEL indicator turns ON, no matter that I put fuel just e
minutes ago.

OK, let's change engine oil and transmission fluid (no info when that
was done before) and filters, too.
Today, on my way to Canadian Tire started ENGINE CHECK light... cool.

They told me, that they can change oil and fluid + filters for $134 -
that's OK.
About the ENGINE CHECK - not sure, about $90/h, but noot sure if they
can fix transmission problem at the site. Doesn' look good to me.

Fluids changed. After that I met somebody, who offer to check the
Engine for me, for free, with tool bought from CTire. Very good, and
then those codes apperaed:
P 0700 - which by the Cirrus book means AT Fault Deected
P 0720 - which i found on the net, that for Chrysler PT Cruiser means
Output Speed Detector Doesen't match the vehicle speed - I presume the
same will be for the Cirrus
and
P 0731 - which I didn't foud nowhere what does it means.

Can anybody help me, please ?

Thanks

 

It sounds like you need a new output transmission speed sensor, a common
replacement item. The part costs about $30 and you can replace it yourself
if you can get under the car. I don't have a Cirrus manual, so I can't
tell you anymore about the replacement. The part should be widely
available at any dealer and you might want to consider replacing the input
transmission speed sensor (separate part #) while you're at it.

P0700 - generic transmission problem code. If you can get codes on your
odometer, this may be the only one you see.
P0720 - output speed sensor as you noted. Even without this specific code,
the combination of limp mode and speedometer not working gives a fairly
good idea your output sensor is shot.
P0731 - First gear incorrect ratio. Most likely related to output sensor
failure and set when the car initially shifted into first gear without a
working sensor.

These codes may set the MIL (check engine) light themselves, (without
manual I can't tell you for sure), so fix them first - replace that
sensor. The low fuel may be set by mileage, which is hard to compute
without speed (odometer).

All in all, you should be pretty lucky- these sensors are not a big deal.

PLEASE report back what you find. Thanks!

 

Greg, good advice. I have a 99 Cirrus and had an input sensor fail
awhile back. I replaced both sensors at the same time, very simple job.
The output sensor can be done from under the front drivers side and the
input sensor was easier to get at by removing the hold down screws for
the transmission control module and moving it up and out of the way.
The input sensor is located between the cooling lines. A 1" open end
wrench worked well on the output sensor and a 1" deep socket worked
well on the input.

Good luck!
Lou G

 

Thank you Greg for the information.

The old sensor was with a lot of metal on it, which I cleaned and put
it back. Car was still hot and it looked like it should be OK -shifted
all gears, speedometer was working. On the next day morning, on cold
start, the sensor wasn't working again, so I went to the dealer. On my
way back, after 20 km driving, suddenly sensor started to work again
and instead of driving with 3000 rpm in 2nd gear it shifts all gears,
as usual. Strange, huh. Anyway, I replaced the sensor and hopefully
that will fix this trouble in the system.
It cost me $44 CAD from the Chrysler dealer. Now it works good, but
Computer is still in training period - I took out the battery (-) end
and that reseted the memory and erased error messages which were stored
there.
Next week I'll have a long trip and after that I'll post an update on
this topic.

Thank you Lou for this easy way of access to the output sensor.
Unfortunately I found it myself after I followed instructions from the
Chrysler's book (on that time this web site wasan't updated yet with
your message), which means:
-remove Air Filter
-remove Transmission module
-remove the Computer
After that, actually there was no access from the top for the Output
sensor. Cool.

So after I saw the location of the sensor, I removed the battery cover
and with the wheels turned for right turn I've got full access to the
sensor. Actually instead of 90-100 minutes working from the top (and
asking yourself "well, after I put this Computer back..."), you can
remove the battery cover under the front right fender for 2-3 minutes,
change the sensor, close and finish in less than 10 minutes. And you
can do that on your parking spot.

Now I have to get the right tool for the input sensor, just in case.

All the best to you guys,
Mitko

 

Cool! I'm glad it worked out.

 

Update: after 1000 km with the new Otput Speed Sensor everything looks
and works fine

 

Excellent. Glad everything worked out and thanks for posting the
followup!