2019 Trailhawk Elite 2.0T Olive Green Metallic Pearlcoat
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"Attaboy"...LOL!!!
More like this, just as fast, but much more controlled and refined than the original GT40...šš
"Attaboy"...LOL!!!
that looks like a lot of fun!"Attaboy"...LOL!!!
More like this, just as fast, but much more controlled and refined than the original GT40...šš
Hmmmm. When they say 'dead as a doornail', does that just mean the Jeep won't start, or that the battery is dead, confirmed by their GR8 machine ?The shop foreman is stumped.
Brought the battery back from AutoZone and told the shop guy what had happened. That evening, he put it back in my Cherokee and not only did it test good, like AutoZone had said, but it started right up. Came in the next morning to get to work on diagnosing my issues and it was dead as a doornail.
Took the battery back out, left it on a charger all day, and tested it - good. Left it on the shop floor all night and when he came back in the morning, it still tested good, so in the Cherokee it went and it started right up.
No idea where the problem is because he's only measuring 30ma or so in draw with the ignition off.
Any guesses? He's not sure where to go from here, which isn't encouraging, given that this is a dealer we're talking about.
-Rob
It's a Duralast Platinum from AutoZone. $240. Nothing like the X2s recommended here, which I'll probably go for next time, despite the $100+ difference.I haven't figured out exactly what battery you have.
A really good thin plate AGM battery is going to cost a lot more than $200.
Wish I still had the first test strip they gave me, but I do remember it showed 12.9A, and only 244CCA. The AutoZone guy made a big deal out of the fact that the strip showed they were testing it as a 700CCA battery (vs. the 850CCA it's rated for), but I don't think that changes the results at all. In any event, both AZ's electronic automatic tester as well as an old fashioned analog load tester he pulled off the shelf to double check showed it good, which apparently it was - at least enough to start my Jeep later that evening.Hmmmm. When they say 'dead as a doornail', does that just mean the Jeep won't start, or that the battery is dead, confirmed by their GR8 machine ?
30mA draw is minimal... so unless something wakes up in the middle of the night ?... it's not parasitic drain.
Do you have more specifics on the battery tests ? Remaining CCA and state of health are the more telling ones and, in your particular case, state of charge would be interesting to see also.
244CCA remaining? That battery needs to be replaced...It's a Duralast Platinum from AutoZone. $240. Nothing like the X2s recommended here, which I'll probably go for next time, despite the $100+ difference.
Wish I still had the first test strip they gave me, but I do remember it showed 12.9A, and only 244CCA. The AutoZone guy made a big deal out of the fact that the strip showed they were testing it as a 700CCA battery (vs. the 850CCA it's rated for), but I don't think that changes the results at all. In any event, both AZ's electronic automatic tester as well as an old fashioned analog load tester he pulled off the shelf to double check showed it good, which apparently it was - at least enough to start my Jeep later that evening.
I know exactly what you're saying about slow starting as the battery goes - BTDT a couple of times. This was quick.
-Rob
One thing is for sure... If AutoZone set the baseline at 700CCA, it could explain why it won't test 'bad'. Your Duralast Platinum is rated for 850CCA and that's what they should use. I've said it here a few times, I question the CCA rating system... because I think the OEM battety's rating is low, while seemingly identical aftermarket batteries sport 800 or 850CCA... but, if they test a Duralast Platinum, they need to set the baseline at 850, not 700...No kidding. Thatās what it tested on the dealerās machine, but not on AZās and was good on the dealerās machine after being charged for 6 hours and NOT put back in the vehicle in the interim.
The question is whether it was just severely discharged in the first (and second) place, or whether itās actually damaged.
My issue is, Iām not going to drop $250-350 on a new battery because AZ wonāt honor the replacement warranty on this one if we canāt determine why it crapped out in the first place.
-Rob
Point of clarification - it was the dealer's machine that was set for 700 (when it tested bad), not AZ's. That's why I was suspicious that the AZ guy didn't really have a handle on what he was talking about when he suggested that's why the dealer's machine tested it bad.One thing is for sure... If AutoZone set the baseline at 700CCA, it could explain why it won't test 'bad'. Your Duralast Platinum is rated for 850CCA and that's what they should use. I've said it here a few times, I question the CCA rating system... because I think the OEM battety's rating is low, while seemingly identical aftermarket batteries sport 800 or 850CCA... but, if they test a Duralast Platinum, they need to set the baseline at 850, not 700...
Wow. Alternator, huh... A very rare problem on the Cherokee.UPDATE - Just talked to the dealer. Alternator is bad. Already approved by MaxCare, but 3-5 days to get the part. Don't know how it could take that long since RockAuto has a MOPAR alternator in stock, but since I'm not paying for it... whatever. I just hope they think to check the cables and belt/tensioner when they install it so I'm not back next month with the same problem.
Question for the hive mind - if it's the alternator (and I don't doubt that it's gone bad), why would an otherwise "good" battery, being attached overnight, drain fully when the draw was measured at only 30mA? I'm thinking I might treat myself to one of these vaunted X2 units frequently recommended here - just to be on the safe side.
-Rob
Yikes... The X2 Power is not $400 yet, but it's getting there :-(Refer to Post #34. Since the alternator really is bad that is good to know.
Generally when a diode in the alternator starts working as a resistor then that is when the alternator constantly draws current from the battery.
Maybe the bad alternator diode current is not included in the parasitic drain, I just don't know.
When you buy an X2 Power battery order it online and get a discount, provide your email address and cell phone number and you will get more discounts.
Of course they will send you text messages, just block the phone number.
They will want a core which really should be a Group 94R. The X2 Power is now more than $400.
Take pictures of the new battery. Get the date the battery was manufactured. Batteries Plus Bulbs should be able to tell you this.
You might want to modify the battery wrap so you can remove it without having to remove the battery cables.
I let my Jeep dealer install the battery. They did it for free. It isn't like I don't already spend a lot of money there.
I've seen motors that had an open or short only when in a certain position. Failures like this are usually caused by a high-voltage surge, like a lightning strike. More often than not a motor hit by lightning has a burnt-out brush causing it not to start running when in a certain position. Get it started and it seems to work fine. However, a surge can also cause a bit of molten metal to protrude and make intermittent contact with parts not intended. When the motor stops in a certain position, it pops the circuit breaker. Otherwise, it works just fine. Great fun to troubleshoot!Question for the hive mind - if it's the alternator (and I don't doubt that it's gone bad), why would an otherwise "good" battery, being attached overnight, drain fully when the draw was measured at only 30mA? I'm thinking I might treat myself to one of these vaunted X2 units frequently recommended here - just to be on the safe side.