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CODE P1634

23K views 21 replies 7 participants last post by  Nash  
#1 ·
So I’ve had the 2014 (MY15) TH 3.2 for 15 months now and only 78,000klms. No issues up to now.
Today the wife said the car was slow to start and then really clunked into gear and then got the “service transmission and parking brake” messages. It did drive home.
I checked it out a while later and it started ok and backed out of the garage and in again no problem.
However the CEL yellow engine light was on.
A while back I bought a BlueDriver scan tool and used it for the first time today. Got the one code; P1634 TCM Internal - Internal Watchdog performance.
Image


So it’s something with the Transmission Control Module…?

A couple of weeks ago it was slow turning over when I left the tailgate open a bit to get a fridge in. And once or twice since then it’s been slow to start also.
Im wondering if it’s possible the battery could be the issue or is that just wishful thinking…? Over here I’m getting quotes for between $490 and $600 for a new one but I don’t mind that if it’s needed. I guess I should get the battery tested first.
Just hoping it’s not a serious issue with the Tranny.
 
#2 ·
Price seems steep for a battery. I personally just got the agm that Costco offers group 94 or whatever, for like $200 and have been happy ever since. I am sure the x2 agm is better but costcos agm works fine for me at a more affordable price.

It very well could be the battery. I’ve had service engine/service 4wd messages that have gone away since I replaced my battery with a new one, and also making sure there’s a good contact on the battery posts to the terminals. Personally I use(d) deoxit and deoxit gold on my battery terminals and haven’t had any issues starting up or any weird issues like service 4wd messages.

(Off tangent but I have the boredom to share my experience): also I never have any issues filling up gas, even if I go past the first click. Just a rubber mallet to the underside of the gas tank here n there, some chevron complete fuel system cleaner, some star tron fuel tank cleaner and enzyme fuel treatment, and a new gas cap and that common problem went away for me for quite some time.
 
#6 · (Edited)
I could be wrong... but OP said 'Paid for the juice', I'm guessing that's a new battery ? Batteries are expensive Down Under...

Edit: nah I was probably wrong... 'servo' means gas station, so paid for gas is probably what happened, haha..

Yes, have that battery tested for sure.
 
#7 ·
So I’ve had the 2014 (MY15) TH 3.2 for 15 months now and only 78,000klms. No issues up to now.
Today the wife said the car was slow to start and then really clunked into gear and then got the “service transmission and parking brake” messages. It did drive home.
I checked it out a while later and it started ok and backed out of the garage and in again no problem.
However the CEL yellow engine light was on.
A while back I bought a BlueDriver scan tool and used it for the first time today. Got the one code; P1634 TCM Internal - Internal Watchdog performance.
View attachment 220157

So it’s something with the Transmission Control Module…?

A couple of weeks ago it was slow turning over when I left the tailgate open a bit to get a fridge in. And once or twice since then it’s been slow to start also.
Im wondering if it’s possible the battery could be the issue or is that just wishful thinking…? Over here I’m getting quotes for between $490 and $600 for a new one but I don’t mind that if it’s needed. I guess I should get the battery tested first.
Just hoping it’s not a serious issue with the Tranny.
Hello,

You might want to take a look and see if this TSB applies to your situation, even though the document is for the U.S. market.

https://static.oemdtc.com/TSB/21-001-18.pdf
 
#9 ·
Took the car in to get the battery checked today and yes it’s a “replace battery” message on the tester.
Was only showing 383 cca’s out of the 800 but was still showing 12.4 volts.
Yet the car started and ran fine again today on the way in so I’m wondering how it can do one thing one day like throw messages and slow start and clunk into gear and then be fine the next time…?
Before I changed the battery I checked again with the BlueDriver and this time scanned ”all systems” instead of just the CEL light system like yesterday and this time got 13 codes across all different areas from anti lock brakes, DTC, BCM steering lock etc.
Anyway I changed the battery, cleared the codes and went for a spin and all seems good. Got a couple of messages; 4WD temporary not available and service parking brake first up but gone on restart. Had to re pair the mobile as well. I will give it a few days and see how it’s going.

The battery I got was a Varta F21 AGM Dynamic for those interested and cost $510 AUD which was the best price I could find. It’s got a 3 year warranty for my SS system but 42 months if not SS.

And yes Mark, juice is petrol to me but I’m originally from England it’s not an Aussie thing 🙂
 
#10 ·
I’m wondering how it can do one thing one day like throw messages and slow start and clunk into gear and then be fine the next time…?
Our Cherokees can do some really strange things with even the slightest of voltage irregularities. We've seen so many, completely random and different things happen, and there's really no rhyme or reason. Wow, batteries are expensive down there...😎
 
#16 ·
Just an update.
Since we had the car the stop start has never worked and I assumed it was turned off in some setting somewhere. As I don’t like it I never looked for how to turn it on.
However after a couple of days with the new battery it now works and we turn it off with the button on the dash. So after having no stop start for over a year the new battery has now made it work…
I‘m assuming the battery was never strong enough to activate the SS?
 
#17 ·
A year without ESS (stop/start), if only battery related, is quite long, but yes it can happen.

ESS is an unintended battery health monitor. Battery health is one very important parameter for Stop/Start, and when the battery fails to reach set threshold values, it just stops working with a 'Battery charging' message in the center display. As battery health declines, ESS will take longer and longer to come online, up to the point it just refuses altogether ; when you reach this point, you usually have a few months left on the battery before you get into the weird stuff, like 4WD temporarily unavailable, steering assist disabled, etc... up to the engine quitting while driving.
 
#21 ·
How's the ground strap look??? Living in Canada, if it's never been changed it's probably looking pretty green and corroded. Also maybe get the battery tested, and double check all connections and grounds...😉😁

https://www.jeepcherokeeclub.com/posts/3034667/