Pacifica P0700, P0720 - tricky issue resolved
#11
01-28-2013, 03:43 PM
You can check the alternator by disconnecting the field wire. The car will run on pure battery power. I drove for less than 5 minutes but that was enough to tell the alternator was the issue. As soon as I plugged it back in, the problem returned. In the Town & Country, it's a pain to replace the alternator but it's been fine ever since.
#12
08-07-2013, 05:12 PM
Error Code P0700, P0720, P0731, P0720 - WRONG!
After reading the article “Pacifica P0700, P0720 - trickyissue resolved” I was stunned. My wife and I were about to either trade-in ourcar or purchase a new Transmission as (3) other mechanic shops had suggested,including Chrysler. All insisting it was the transmission.
We also had these issues leading up to it:
“experiencing weird speedo issues for the past year alongwith the hard shifting. The worst was always at idle while stopped with thetransmission in drive. The speedo would jump up to 20 and the transmissionshift gears while sitting still.”
Then the mechanic shops told us we had codes p0731a – p0732a(gear 1 and gear 2) and that the transmission was trashed.
BOTTOM LINE: I checked the alternator with the volt meter.It was dying. One minute it was ok then it was pulling energy from the battery.– I replaced the Alternator. Oddly enough the New one came with a huge warningsticker stating that “This alternator can hugely effect the sensitive computer equipmentof this vehicle!”
After replacing the alternator (the computer reset due tothe fact the battery needs to be disconnected during removal and installationof the alternator) I am VERY PLEASED to say that all transmission codes haveremained off, and all malfunctions are gone. Even the dreaded REPLACE GAS CAPis gone. We have been driving for days now and not an issue. Ill will post backif any codes from the past issue comes back. $3000.00 rip off cost me $240.00and my time. Thank you for the post!
https://www.chryslerforum.com/forum/chrysler-pacifica-15/pacifica-p0700-p0720-tricky-issue-resolved-15556/
#13
08-08-2013, 01:45 AM
I had a similar issue where I was having transmission issues and ECU was throwing transmission codes. I went to have alternator checked and it turned out to be dead battery. Replacing the battery fixed the issue. Here is the link to my original post:
https://www.chryslerforum.com/forum/...0-p0846-19669/.
Pacifica has many many issues but it is very rare to hear a real mechanically transmission related issue with this car.
https://www.chryslerforum.com/forum/...0-p0846-19669/.
Pacifica has many many issues but it is very rare to hear a real mechanically transmission related issue with this car.
#14
08-08-2013, 11:10 PM
Just posting this to share incase someone else has the same problem.
Symptoms: Speedo reads +mph when sitting in drive, reverse with foot on the brake - usually showed between 10 and 25mph on the speedometer. Car 'clunked' when shifting into reverse and would feel like it was pulling hard against the brakes with an elevated idle.
Took it to AAMCO, and they replaced an output speed sensor (~150$). 4mo later, same thing, and I take it back. This time they say the code isn't there, and they can't reproduce the problem, but there is the generic transmission code P0700, and it is clunking into gear, and the fluid smells funny, etc, and they try to put the hard sell on me to pull the trans and take a look (700$ to take a look). I told them no thanks.
Brought the car home, bought a code scanner (been needing one anyway), and sure enough, code P0720, output speed sensor. Bought one at autozone for 16$, replaced it myself.
Several weeks later, same condition. Dropped the trans pan and changed the filter/fluid because there was some metal dust on the magentic tip of the speed sensor. No dice.
After messing with the car for a while, I realized it would only do this right at startup, and then the condition would go away, until I turned on the air conditioner (summer in phoenix so this is always on may-oct) or the headlights.
Had my charging system checked, and they got a "Excess Diode Ripple" condiiton on my alternator. Picked one up from the local auto recyclers for 40$, and now the car is running great again with no p0700 or p0720. It turns out that when a diode in your alternator goes out, it can create basically EMI that can freak out various sensors in the car.
So much for the shot transmission and 700$ to take a look. If I would have let them do that they obviously would have rebuilt it costing me thousands, and I would still have the same problem. Lol AAMCO, and yes, they will be hearing about this.
Also, one note, when the condition would happen, it would throw codes p0700 and p0720. Once these codes were thrown the trans would shift bad, harsh from park into reverse. Pretty sure the car got stuck in limp-home mode once, but all of this would go away when I used the scanner to reset the CEL.
Anyway, hope this helps someone else and saves them some $$...
Oh yea, one side note, the alternator job is trivial, except for the belt tensioner, which was a total freaking nightmare. Get in there and figure out if you can get a tool on it before you tear the rest of the car apart. I had to use a 3/8in socket driver, but a normal ratchet wrench was too big, so I used one that was just a bar with the 180* swivel, that was the only thing compact enough to get in the tensioner, I then had to use a piece of pipe to get enough leverage, pushing hard with the left hand, holding the tension off of the belt, while getting the belt on 1 handed, and this was from under the car. I wasn't sure I would be able to pull it off, and it was a challenge. Im sure there is a better tool for the job, but I didn't have it...
Symptoms: Speedo reads +mph when sitting in drive, reverse with foot on the brake - usually showed between 10 and 25mph on the speedometer. Car 'clunked' when shifting into reverse and would feel like it was pulling hard against the brakes with an elevated idle.
Took it to AAMCO, and they replaced an output speed sensor (~150$). 4mo later, same thing, and I take it back. This time they say the code isn't there, and they can't reproduce the problem, but there is the generic transmission code P0700, and it is clunking into gear, and the fluid smells funny, etc, and they try to put the hard sell on me to pull the trans and take a look (700$ to take a look). I told them no thanks.
Brought the car home, bought a code scanner (been needing one anyway), and sure enough, code P0720, output speed sensor. Bought one at autozone for 16$, replaced it myself.
Several weeks later, same condition. Dropped the trans pan and changed the filter/fluid because there was some metal dust on the magentic tip of the speed sensor. No dice.
After messing with the car for a while, I realized it would only do this right at startup, and then the condition would go away, until I turned on the air conditioner (summer in phoenix so this is always on may-oct) or the headlights.
Had my charging system checked, and they got a "Excess Diode Ripple" condiiton on my alternator. Picked one up from the local auto recyclers for 40$, and now the car is running great again with no p0700 or p0720. It turns out that when a diode in your alternator goes out, it can create basically EMI that can freak out various sensors in the car.
So much for the shot transmission and 700$ to take a look. If I would have let them do that they obviously would have rebuilt it costing me thousands, and I would still have the same problem. Lol AAMCO, and yes, they will be hearing about this.
Also, one note, when the condition would happen, it would throw codes p0700 and p0720. Once these codes were thrown the trans would shift bad, harsh from park into reverse. Pretty sure the car got stuck in limp-home mode once, but all of this would go away when I used the scanner to reset the CEL.
Anyway, hope this helps someone else and saves them some $$...
Oh yea, one side note, the alternator job is trivial, except for the belt tensioner, which was a total freaking nightmare. Get in there and figure out if you can get a tool on it before you tear the rest of the car apart. I had to use a 3/8in socket driver, but a normal ratchet wrench was too big, so I used one that was just a bar with the 180* swivel, that was the only thing compact enough to get in the tensioner, I then had to use a piece of pipe to get enough leverage, pushing hard with the left hand, holding the tension off of the belt, while getting the belt on 1 handed, and this was from under the car. I wasn't sure I would be able to pull it off, and it was a challenge. Im sure there is a better tool for the job, but I didn't have it...
#16
10-17-2013, 11:51 AM
That's Wild
Similar experience on my 2005 Pacifica (3.5L). I plan to get the Alternator checked at Autozone tonight and if faulty, I'll get a new one and install. If this works, I'll need to buy Travis a beer!!! 
Next thing I need to explore on this site is solution for the massive oil consumption that kills Cats and gunks Butterfly in Throttle Body....
I've heard that's attributable to Piston Ring Notchs aligning and letting oil get into combustion chamber... I asked Chrysler Corp and they said it's typical for their cars to burn 1 quart every 500 miles....
Next thing I need to explore on this site is solution for the massive oil consumption that kills Cats and gunks Butterfly in Throttle Body....
I've heard that's attributable to Piston Ring Notchs aligning and letting oil get into combustion chamber... I asked Chrysler Corp and they said it's typical for their cars to burn 1 quart every 500 miles....
#17
10-18-2013, 05:50 AM
Wild
Alternator test shows bad diodes. CEL shows more 700 series ugly codes. Disconnected field wire from Alternator, smooth shifting an no Speedo craziness. Travis is a genius!!!!! New Alternator on order.
BTW, I also replaced the Output Speed Sensor. Fortunately that was only $18.
Also, thanks for tip on belt tensioner tool. I'll pick one of those up when I do the install.
Appreciate everyone's posts. Clearly the lessons learned from this community are an excellent counter to the risk of the loan mechanic and the training they've received to follow the book when it comes to CEL troubleshooting and corrective action. I wonder how many people got a Tranny rebuild when this happened to them.....
Thanks all for sharing your experiences!!!
BTW, I also replaced the Output Speed Sensor. Fortunately that was only $18.
Also, thanks for tip on belt tensioner tool. I'll pick one of those up when I do the install.
Appreciate everyone's posts. Clearly the lessons learned from this community are an excellent counter to the risk of the loan mechanic and the training they've received to follow the book when it comes to CEL troubleshooting and corrective action. I wonder how many people got a Tranny rebuild when this happened to them.....
Thanks all for sharing your experiences!!!
#18
10-18-2013, 11:06 PM
>>[QUOTE=rbeckler;67828]You can check the alternator by disconnecting the field wire.<<
I asked two shops for their opinion about doing this for testing. The first old timer shop guy said "DON"T do it". Here is the message I got back from another very well equiped and well known shop for top service and repairs.
"That would be a very risky way to do it and could blow several computers at once"
Could they both be wrong ? Maybe Chrysler Tech can add something to this ? Thanks. *BW*
I asked two shops for their opinion about doing this for testing. The first old timer shop guy said "DON"T do it". Here is the message I got back from another very well equiped and well known shop for top service and repairs.
"That would be a very risky way to do it and could blow several computers at once"
Could they both be wrong ? Maybe Chrysler Tech can add something to this ? Thanks. *BW*
#19
10-20-2013, 09:25 AM
Just a ps on this note. New alternator installed. All good! The old alternator was making a slight high pitch whining noise that sounded like a vacuum leak from inside the car. Apparently, that's another indication that an alternator is toasting. Also the voltage output from the bad alternator was fine. It was keeping the battery charged and running all systems. The bad diodes were just freaking out the computer. New alternator was $240.00 at Autozone. Install was pretty simple, but the belt tensioner - which must be engaged from under the car (remove the belt splashguard - and plan to replace all plastic fasteners because they may all break) - wasn't all that easy to move with a 15MM open end wrench. Fortunately I had a helper pop the belt on the alternator pulley while I got two hands on the wrench. Might have been a 1 man job if I'd of jacked the car up to get enough clearance to put a pipe on the wrench for more leverage....
#20
10-26-2013, 05:00 PM
.... Install was pretty simple, but the belt tensioner - which must be engaged from under the car (remove the belt splashguard - and plan to replace all plastic fasteners because they may all break) - wasn't all that easy to move with a 15MM open end wrench. Fortunately I had a helper pop the belt on the alternator pulley while I got two hands on the wrench. Might have been a 1 man job if I'd of jacked the car up to get enough clearance to put a pipe on the wrench for more leverage....
Next thing I need to explore on this site is solution for the massive oil consumption that kills Cats and gunks Butterfly in Throttle Body....
I've heard that's attributable to Piston Ring Notchs aligning and letting oil get into combustion chamber... I asked Chrysler Corp and they said it's typical for their cars to burn 1 quart every 500 miles....
I've heard that's attributable to Piston Ring Notchs aligning and letting oil get into combustion chamber... I asked Chrysler Corp and they said it's typical for their cars to burn 1 quart every 500 miles....
Last edited by Raindrop; 12-12-2013 at 04:45 PM.