Self-Inflicted..Electrical Issue

[PaCowboy]

Son #2 has a ‘21- 1500 that he ran the battery down on and they connected the jumpers from another Ram, but reversed the polarity…

after replacing a blown fuse or two, seemed to run okay but now acting quirky, temp gage goes up and engine service light comes on, but when shut off, gage drops immediately and service light is off.
Also, 4-wheel drive randomly engages/disengages without being turned on.

Any thoughts?

 

[4xdad]

Damaged computer

 

[Sherman Bird]

Son #2 has a ‘21- 1500 that he ran the battery down on and they connected the jumpers from another Ram, but reversed the polarity…

after replacing a blown fuse or two, seemed to run okay but now acting quirky, temp gage goes up and engine service light comes on, but when shut off, gage drops immediately and service light is off.
Also, 4-wheel drive randomly engages/disengages without being turned on.

Any thoughts?

THROW THE JUMPERS away! Get a booster box.

 

[RamDiver]

THROW THE JUMPERS away! Get a booster box.

^^^^^^ This!

Our trucks are rolling microcomputers with a common B+ connection to every module.

Would you hotwire your home desktop PC?

A NOCO GB-40 or equivalent is less than $100 in the US.

.

 

[turkeybird56]

@RamDiver
@Sherman Bird

Hey guys, if he got the fuses blown replaced, would a Hard Reset,. ie., pull negative cable and leave off for hours and discharge also the system possibly help and reset???

Just trying to think outside the box to help the OP

ADDED: I definitely got some mean negative comments towards the OP's son, but that not gonna help. Wonder if they damaged the jumping vehicle also. Friggin RAM electronics are more Finicky than Gilda the Good Witch in OZ.

 

[turkeybird56]

@RamDiver

BOIRD running. Big electrical storm coming. Gotta shut down my modest machine here.

DA BOIRD.

 

[RamDiver]

@RamDiver

BOIRD running. Big electrical storm coming. Gotta shut down my modest machine here.

DA BOIRD.

Don't you have a UPS on the PC?

.

 

[turkeybird56]

Don't you have a UPS on the PC?

.

No. I have whole house power unit I am Neva down for more than 30 seconds. But I also try to better than the average bear ref storms.

 

[RamDiver]

@RamDiver
@Sherman Bird

Hey guys, if he got the fuses blown replaced, would a Hard Reset,. ie., pull negative cable and leave off for hours and discharge also the system possibly help and reset???

Just trying to think outside the box to help the OP

ADDED: I definitely got some mean negative comments towards the OP's son, but that not gonna help. Wonder if they damaged the jumping vehicle also. Friggin RAM electronics are more Finicky than Gilda the Good Witch in OZ.

Back to basics for the OP.

Charge the failing battery and then load test it with a toaster-style load tester like this $18 device from Harbour Freight.

If the battery fails to provide sufficient cranking amps, replace it, charge and load test the new battery. * New batteries should always be charged and load tested, no exceptions, unless the seller has charged them while you wait.

The load test should be completed ASAP on any new battery. Many of the digital load testers used at commercial outlets are prone to false positive results unless they have spent big $ on it.

After confirming the battery is adequate, scan for codes. If you don't have access to a scanner, many auto parts stores offer free scanning services. Ask them to test the alternator while you're there.

Don't drive the truck anywhere if it is suffering from intermittent and erratic electrical faults.
Borrow or buy an inexpensive scanner if you don't own one.

Then post the scanner results. Don't use the DTCs with a parts cannon and start changing parts.
The DTCs are the first step in testing to help with the diagnosis.

.

 

[Papa Red]

Welcome to the forum.

Red

 

[Harley Harrold]

 

[Tominator223]

Try a hard reset on pcm. You might get lucky. Disconnect both cables. Hold them together for 30-45 secs. Should clear everything. Then hook back up. See how it acts

 

[Bighorn_Brown]

^^^^^^ This!

Our trucks are rolling microcomputers with a common B+ connection to every module.

Would you hotwire your home desktop PC?

A NOCO GB-40 or equivalent is less than $100 in the US.

.

I’ve got that exact jumper box. I love it. Has saved me once, and a few others on the side of the road, parking lots, and parking garages… they said they were gonna put one on their “To Get” list.

 

[Hardracer]

I told a guy at work about touching the 2 cables together to drain the system awhile back.His reply was dont do that, its creating a dead short and can fry delicate parts that the components have in them(he said capacitors,diodes), so I searched his words....tuns out his statement was as he said.it also said it's better to just disconnect the cables and let it happen naturally.....what do you guys think?

 

[turkeybird56]

I told a guy at work about touching the 2 cables together to drain the system awhile back.His reply was dont do that, its creating a dead short and can fry delicate parts that the components have in them(he said capacitors,diodes), so I searched his words....tuns out his statement was as he said.it also said it's better to just disconnect the cables and let it happen naturally.....what do you guys think?

Wat lead mechanic at RAM shop told me ref discharging system, especially when doing battery change and IBS relearn. Not taping cables together.

EDIT: OP has not returned after Original Post.

 

[turkeybird56]

^^^^^^ This!

Our trucks are rolling microcomputers with a common B+ connection to every module.

Would you hotwire your home desktop PC?

A NOCO GB-40 or equivalent is less than $100 in the US.

.

@RamDiver

Gonna send email. X2 sent