Tow vehicle struggling to start after towing

[BBandJ]

We are having a new issue with our tow vehicle when towing our Oliver that we have not had in the previous year and half of owning our Oliver. After towing for several hours when I start my tow vehicle the engine has a very hard time starting and it feels like the car battery is not charged enough to start the car. This only happens after towing. I have recently replaced the battery in my tow vehicle and it did not solve the issue. Has anyone had an issue like this? Could the Oliver be drawing too much power from my tow vehicle? I am taking my tow vehicle into the shop next week.

[Ray Kimsey]

I think I would have my alternator tested first.

[SeaDawg]

What batteries do you have? Solar? Are you running the fridge on dc or gas or off when traveling?

Tow vehicle? 

Most modern vehicles simply won't start with a too low battery. Cabin lights and radio may come on, but you may just get a click or nothing when trying to start. I'd also suspect an ignition switch or starter issue, if your truck is fairly new.

[BBandJ]

Standard lead acid batteries and we have solar. We have the fridge in DC but have always done that from the day we picked up our Oliver.

[SeaDawg]

17 minutes ago, SeaDawg said:

Most modern vehicles simply won't start with a too low battery. Cabin lights and radio may come on, but you may just get a click or nothing when trying to start. I'd also suspect an ignition switch or starter issue, if your truck is fairly new.

What's your tow vehicle?

And, what happens when it "struggles" to start?

[BBandJ]

2018 Jeep Grand Cherokee with V8 and the factory tow package from Jeep. It turns over 10 to 15 times and then starts.

[rideandfly]

3 hours ago, SeaDawg said:

What batteries do you have? Solar? Are you running the fridge on dc or gas or off when traveling?

Tow vehicle? 

Most modern vehicles simply won't start with a too low battery. Cabin lights and radio may come on, but you may just get a click or nothing when trying to start. I'd also suspect an ignition switch or starter issue, if your truck is fairly new.

SeaDawg asked the first thing I thought about. I personally would not run my refrigerator on DC, would run it on LP gas.

[Frank C]

You mentioned that you already replaced the battery in your tow vehicle, was the alternator checked out as well?   It may not be charging your tow vehicle battery properly. 

[BBandJ]

It sounds like I need to have my alternator checked. That is very helpful!

[SeaDawg]

When you have this issue, is the trailer connected to the Jeep, and the refrigerator off, or on, on dc? If you're connected, and trailer is trying to pull power, for dc fridge, I'd guess it might(?) do that, sensing enough power,, then losing it to the dc fridge,, but otherwise,  I think with a low battery, you should just get nothing .

My daughter has a 2017 grand cherokee.  Recently, when her starter battery was low, overnight,, but hey,, original battery,, she got nothing but radio and fan. Not that slow trying of several times, like the old days. With hers, she has enough power, or not. Start cuts out.

Btw, hers has two batteries, and it's a pita, both under the passenger seat. One for starter and most systems, one for start/stop. To replace the starter battery properly,  you must have 12v available with a bypass device while doing the swap, to avoid losing the vehicle's programming. This could possibly also be your issue, if new jeep battery was improperly installed. Idk. Just another guess. You "might" have lost some program,  if improperly installed.

(Actually,  not that difficult to do the swap,  except for battery access. Her boyfriend did the battety swap, without help, with the loan of our Viking jumpbox.) And, it has that vent tube thing, as well.

Also check cable ends for corrosion, and proper tightening. You have to be a contortionist to actually get to my daughter's batteries, under the passenger seat. Really stupid design, imo.

However, it's a really nice suv, and she loves it.

And, of course, check alternator @FrankC, starter, and ignition switch.

Oh, and low battery in the keyfob for the ignition. You can test that by trying to start with the keyfob touching the right spot. Even with a dead keyfob  battery, you can start the car.  Kind of a fail safe feature.  That's another issue she's experienced. 

 

[ScubaRx]

If the alternator checks out, my guess is the battery's in the Oliver are shot (likely from running the fridge on DC for the past few years). If you are not unplugging the trailer when you stop, in some vehicles the trailer battery's and the truck battery will try to equalize thus bringing the truck battery down to the level of the trailer.