Swapped Cables On Battery, Now Vsc And Check Engine Lights On

NEBCO · January 1, 2009

battery appeared to be going dead (it's the original on an '03) so i pulled it and had my son pick up a new one while he was out. in the meantime, i got a fire call (i'm a volunteer firefighter), so i tossed the old one back in (i had it on a charger just in case) and in my haste i swapped the cables- put the neg cable on the positive terminal, and vice versa. bad news.

after a little diagnostic work, i found that the charging system fuse (#62- it's a big sucker at 140 amps) was blown. i replaced it, and put in the new battery. car still wouldn't start, so i found that one of the other fuses (a small 10 amp atm style fuse) related to fuel injection was out. i replaced that fuse also, and now the car starts and idles normally, but only barely accelerates. if i put it in park and hit the gas, i can only get 2500 rpms.

i also have a dash warning to check the vsc, i have an icon on the dash that says vsc off, and the check engine light is on. radio display is completely dead, but i suspect that issue is not related to my acceleration issue.

any thoughts on what the acceleration problem is? towing it to the dealer is a major problem because i live in the sticks, and the tow would be big bucks.

thanks in advance.

btw, if anyone in the future searches for how to replace fuse 62, here's the trick- there are four plastic tabs that hold the fuse box together. two tabs are on the front side of the box, and two on the back. take a regular screwdriver and press straight down on the movable part of the tab and the fuse box will start to separate. it helps to do both the driver's side tabs at the same time, then do the passenger's side at the same time. with the box separated, use a 10mm ratchet to remove the bolt holding the wire to the bottom of fuse blade closest to the front of the car. use an 8mm ratchet to remove the bolt holding the wire on the fuse blade towards the back of the car. be careful not to lose the bolts into the bowels of the engine compartment. the fuse will now slide out the top easily. replace and reverse the process.

landar · January 1, 2009

Ouch! Sorry to hear about the polarity reversal. Thats gotta be one big "Oh S***" :o

The first order of business would be to find out which CEL code(s) is being indicated.

OBDII readers are relatively cheap. You might want to buy one, borrow one or hobble into

Autozone to have them read the code(s).

NEBCO · January 1, 2009

well, went through all the fuse boxes this afternoon- found one bad fuse for the stereo. the weird thing is the car now drives fine with no CEL or VSC issues. ABS works as it should, and VSC works when on. i don't know if letting it sit overnight did something, or if the process of removing all the fuses and replacing them caused something to reset.

radio is still dead, but that appears to be the only problem. it will now go to the dealer, and i'll have the codes pulled.

happy new year!

1990LS400 · January 2, 2009

The VSC on my 2000 LS400 seems to reset itself within a day or two after I change a battery if I do not perform the VSC reset procedure. I installed a new battery last Sunday and was surprised that the usual "Check VSC" message was not displayed when I started the car with the new battery -- must have reset itself immediately. At least on my car, one of the first signs of battery failure has been for the "Check VSC" and VSC warning light to come on.

Does your LS430 have plastic battery cable end covers that snap into place after the cable ends are attached to the battery terminals? The positive battery cable end should have a red plastic cover with a plus (+) sign on it and the negative battery cable end should have a black plastic cover. Car batteries have a plus (+) sign stamped by the positive terminal and a negative (-) sign stamped by the negative cable. I know these battery cable end covers tend to get removed and lost so getting replacements would be good if yours are missing.

Lejas · May 19, 2015

I have an identical problem. I checked every fuse, replaced all of the fuseable links, and the big 140A fuse was blown. This brought the car back to life, sort of, but the AC Navigation / Radio are all dead. I've searched a lot of forums, and found similar problems, but no solutions about the radio/nav/ac unit. I was really hoping this was just a fuse, but double checked them with a tester. I have the Check Engine and VSC lights on as well, with 2000 max rpms. I would love to know what ultimately solved your problem.

billydpowell · May 25, 2015

Hi Brent, this thread is 6 years old, so you might not get the OP comments but someone will probably jump in to help you.... nothing like that has ever happened to me., so I am no help...

landar · May 25, 2015

Brent, it might help to know why your 140A fusible link was blown. Did you reverse the battery cables during a jump? Those big fuses do not blow unless something fairly catastrophic happens. And it might be that you blew out an ECU of some sort, the one controlling the NAV controls.

Also, it is not enough, IMO, to just check fuses. You have to get a voltmeter on the fuse itself to verify that 12V is present.