My partner took my '98 LC on a 900 mile trip this weekend, and didn't quite make it home. Yesterday she started getting an intermittent battery light after filling up on fuel, but after advising her to check the battery terminals for corrosion and a good connection she cleaned them up and re-tightened the terminals (they were pretty filthy and the positive was a bit loose). That seemed to solve the problem and after driving a few more hours, she stopped for the night. The truck started up this morning without issue but after driving for about an hour the truck completely died while on the highway and she managed to get over to the shoulder. She did say the ABS light came on moments before it died. It would not restart without a jump, and once jumper cables were disconnected it would immediately die. She put a multimeter on the battery and it only read 7 volts, so the question is was this a failed alternator that drained the battery? I've noticed a faint squeak coming from something on the accessory belt for the last couple months, and it is the original alternator to the best of my knowledge. I don't want to just throw a new battery at the problem in case the alternator runs that one down, but 7 volts is exceptionally low which makes me feel the battery could be at fault as well. Any input is appreciated! The truck is on a flatbed right now coming home and I've got an alternator and battery arriving Tuesday morning, but some insight would be helpful.
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- Thread starter
- #3
I've owned the rig for 2 years and the battery came with it, and I believe it had a manufacture date of 2016 or 2017
Last edited:
ramangain
Clarksonian disciple
New alternator and battery, just do it right the 1st time
I think the alternator and battery both might need to be addressed. If the alternator wasn't able to keep it running while driving on the highway it's almost certainly gone unless there's a loose connection somewhere. And 7 Volts on the battery! I would suspect dead cells in the battery if it got that low, but maybe I'm wrong and all it needs is a recharge. I'm sure batteries last longer up in BC, but down here in AZ, we typically don't get past 2 years of life. 4 to 5 years of battery life is a good long time in my book, so it's probably a good time to change it as a preventative maintenance measure even if it turns out to be good.
If it were me, I would fully charge the battery first and see if it will indeed charge up to its normal voltage. If not, I'd change the battery. If it does charge up, the next thing I would do is check the ground connections from the battery to the body and body to the engine. Also, check the alternator cable to the positive battery terminal. If any of those connections are loose, the alternator won't do its job. If all of those were already making a good connection, I would go ahead and replace the alternator.
If it were me, I would fully charge the battery first and see if it will indeed charge up to its normal voltage. If not, I'd change the battery. If it does charge up, the next thing I would do is check the ground connections from the battery to the body and body to the engine. Also, check the alternator cable to the positive battery terminal. If any of those connections are loose, the alternator won't do its job. If all of those were already making a good connection, I would go ahead and replace the alternator.
- Thread starter
- #6
I'll check for loose connections once its back home, good suggestion. And yeah, I feel like 7 volts is way beyond the point of no return for a battery. I wouldn't trust it ever again even if I got it back up to normal voltage, so I'm just going to put the new one in regardless. Due to my location I wasn't able to get a Denso alternator, reman or new, until the second week of August, so I had to settle for a parts store Bosch reman in the meantime. If the old unit looks healthy, I'm going to replace the brushes and bearing and just swap that back in when the Bosch dies.
