Possible Alternator Issues
Thread Starter
Pit Crew
Joined: Feb 2016
Posts: 161
Likes: 10
From: South Carolina
Possible Alternator Issues
So my 2003 Lexus Is300 died tonight while driving 50mph with my husband and 2 little girls in the car.
The trigger was the turn signal.
I went down and ran diagnostics on it, but no alternator malfunction is showing. I’ve noticed the gauge on the dash seems a bit lower than it should be... hovering above the line over 9.
I learned that the halogen lights pull a lot of power from the battery, so my assumption is that my alternator is on its way out.
Thoughts? Suggestions? Am I right on, or way off?
Thanks in advance for any input guys!
Sincerely,
Christa
The trigger was the turn signal.
I went down and ran diagnostics on it, but no alternator malfunction is showing. I’ve noticed the gauge on the dash seems a bit lower than it should be... hovering above the line over 9.
I learned that the halogen lights pull a lot of power from the battery, so my assumption is that my alternator is on its way out.
Thoughts? Suggestions? Am I right on, or way off?
Thanks in advance for any input guys!
Sincerely,
Christa
Pole Position
Joined: Nov 2018
Posts: 2,077
Likes: 576
From: CA
You can use a DMM to check for voltage across the battery terminals then from the alternator to battery negative to see if you are loosing power through a corroded cable. Check your terminals. Make sure they are not corroded and tighten down all the way. The Alternator can't charge the bat through crappy connections.
So say for example you jump start it and find that while running it shows 12ish volts, but 13-14ish at the alternator. Then the alternator is good but it's not making it to the battery.
So say for example you jump start it and find that while running it shows 12ish volts, but 13-14ish at the alternator. Then the alternator is good but it's not making it to the battery.
Thread Starter
Pit Crew
Joined: Feb 2016
Posts: 161
Likes: 10
From: South Carolina
Thanks so much for your response! My battery is 12 volts, but did the battery alternator test thing and it lost power using various things... lights, AC.
So I had a test done in the battery and alternator and they think the alternator is bad also... the terminals are clean and good...and it’s a good battery, fully charged...
So um yeah ... damn alternator is failing me 🙁
So I had a test done in the battery and alternator and they think the alternator is bad also... the terminals are clean and good...and it’s a good battery, fully charged...
So um yeah ... damn alternator is failing me 🙁
Driver School Candidate
Joined: Feb 2019
Posts: 11
Likes: 3
From: NC
It could be your crankshaft pulley. When the car is hot and idling, voltage and power steering goes down with a side of belt noise. Was about to replace the alternator but figured to test all the pulleys. My crankshaft pulley was split.
Driver School Candidate
Joined: Feb 2019
Posts: 11
Likes: 3
From: NC
Thanks so much for your response! My battery is 12 volts, but did the battery alternator test thing and it lost power using various things... lights, AC.
So I had a test done in the battery and alternator and they think the alternator is bad also... the terminals are clean and good...and it’s a good battery, fully charged...
So um yeah ... damn alternator is failing me 🙁
So I had a test done in the battery and alternator and they think the alternator is bad also... the terminals are clean and good...and it’s a good battery, fully charged...
So um yeah ... damn alternator is failing me 🙁
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Driver School Candidate
Joined: Aug 2019
Posts: 22
Likes: 1
From: ga
whatever you do, don't replace it with anything other than a denso. I rebuilt mine for 75$. they just don't like to die so they show the smallest of symptoms, first time I had a low voltage I just disconnected it, cleaned and bolted it back up and ran fine for another year, then it finally **** on me. rebuilding it is so much cheaper and better than buying a **** aftermarket
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Thread Starter
Pit Crew
Joined: Feb 2016
Posts: 161
Likes: 10
From: South Carolina
whatever you do, don't replace it with anything other than a denso. I rebuilt mine for 75$. they just don't like to die so they show the smallest of symptoms, first time I had a low voltage I just disconnected it, cleaned and bolted it back up and ran fine for another year, then it finally **** on me. rebuilding it is so much cheaper and better than buying a **** aftermarket
Tomorrow “Lucy” gets a new alternator and they are going to change out the belt since they must take it off anyway... since I have no idea when the belt was changed last... figured kill two birds with one stone... and the shop isn’t charging me extra for replacing the belt, just the part cost.
I am unable to do this work myself.... not the right tools, experience and I live in a condo at the beach... so no work area is available here... and besides I think the old people would frown upon that level of car repair (other than what I have already done here)
so so wish me luck!!!
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