2003 ES300 voltage regulator bad
05-15-18, 06:59 PM
#1
Driver School Candidate
Thread Starter
2003 ES300 voltage regulator bad
I just discovered my voltage regulator is bad. Could this be causing the problems I'm having with my bank 2 camshaft sensor? Did it ruin the sensor or am I just getting the code because of the bad regulator? Do you think there's any permanent damage possible? Thanks for your insights.
05-15-18, 08:33 PM
#2
A bad voltage regulator can cause weird electrical problems. I’ve not had it happen in this car, but in another one.
I don’t think the VR should have an effect on a camshaft sensor, it’s a relatively robust, on/off sensor that some ac ripple voltage should not influence in my thinking (but I’m not an electrical engineer). What a bad VR will effect more readily are more sensitive electronics and if bad enough can damage the ecu. It might be influencing the ecu handling of the sensor signal, though. So it could be doing it, but not directly by action on the sensor itself.
Get it fixed soon and try not to drive the car with a bad VR. These are not terribly hard to rebuild yourself if you have a workbench and basic skills. If not, you are next best finding an alternator shop/auto electric shop and having them rebuild it; you will get a more reliable and better job than buying a rebuilt unit online or from the local auto parts stores. Unfortuantely that means having the car down a few days vs. dropping in instantly like a rebuilt one from the store. But if you can live w/o the car a few days and take that route, the cost will be comparable and the quality and reliability much better. There is a really high failure rate on chinese and Mexican rebuilt units, which is about all you can find at auto parts stores these days.
Getting the alternator in and out of these is pretty easy. Just pay attention before you take it apart as to how the adjuster bolt assembly works, it isn’t hugely intuitive and can go together incorrectly easily.
I don’t think the VR should have an effect on a camshaft sensor, it’s a relatively robust, on/off sensor that some ac ripple voltage should not influence in my thinking (but I’m not an electrical engineer). What a bad VR will effect more readily are more sensitive electronics and if bad enough can damage the ecu. It might be influencing the ecu handling of the sensor signal, though. So it could be doing it, but not directly by action on the sensor itself.
Get it fixed soon and try not to drive the car with a bad VR. These are not terribly hard to rebuild yourself if you have a workbench and basic skills. If not, you are next best finding an alternator shop/auto electric shop and having them rebuild it; you will get a more reliable and better job than buying a rebuilt unit online or from the local auto parts stores. Unfortuantely that means having the car down a few days vs. dropping in instantly like a rebuilt one from the store. But if you can live w/o the car a few days and take that route, the cost will be comparable and the quality and reliability much better. There is a really high failure rate on chinese and Mexican rebuilt units, which is about all you can find at auto parts stores these days.
Getting the alternator in and out of these is pretty easy. Just pay attention before you take it apart as to how the adjuster bolt assembly works, it isn’t hugely intuitive and can go together incorrectly easily.
05-15-18, 08:40 PM
#3
Driver School Candidate
Thread Starter
A bad voltage regulator can cause weird electrical problems. I’ve not had it happen in this car, but in another one.
I don’t think the VR should have an effect on a camshaft sensor, it’s a relatively robust, on/off sensor that some ac ripple voltage should not influence in my thinking (but I’m not an electrical engineer). What a bad VR will effect more readily are more sensitive electronics and if bad enough can damage the ecu. It might be influencing the ecu handling of the sensor signal, though. So it could be doing it, but not directly by action on the sensor itself.
Get it fixed soon and try not to drive the car with a bad VR. These are not terribly hard to rebuild yourself if you have a workbench and basic skills. If not, you are next best finding an alternator shop/auto electric shop and having them rebuild it; you will get a more reliable and better job than buying a rebuilt unit online or from the local auto parts stores. Unfortuantely that means having the car down a few days vs. dropping in instantly like a rebuilt one from the store.
Getting the alternator in and out of these is pretty easy. Just pay attention before you take it apart as to how the adjuster bolt assembly works, it isn’t hugely intuitive and can go together incorrectly easily.
I don’t think the VR should have an effect on a camshaft sensor, it’s a relatively robust, on/off sensor that some ac ripple voltage should not influence in my thinking (but I’m not an electrical engineer). What a bad VR will effect more readily are more sensitive electronics and if bad enough can damage the ecu. It might be influencing the ecu handling of the sensor signal, though. So it could be doing it, but not directly by action on the sensor itself.
Get it fixed soon and try not to drive the car with a bad VR. These are not terribly hard to rebuild yourself if you have a workbench and basic skills. If not, you are next best finding an alternator shop/auto electric shop and having them rebuild it; you will get a more reliable and better job than buying a rebuilt unit online or from the local auto parts stores. Unfortuantely that means having the car down a few days vs. dropping in instantly like a rebuilt one from the store.
Getting the alternator in and out of these is pretty easy. Just pay attention before you take it apart as to how the adjuster bolt assembly works, it isn’t hugely intuitive and can go together incorrectly easily.
05-15-18, 09:23 PM
#4
Understood; when the ES alternator was bad 3 years ago, I was in the same situation and used a rebuilt from O'Reillys. Already replaced that one once since then (so make sure you purchase from whatever store has a lifetime warranty). My SUV had the bad VR about the same time. I rebuilt it myself for 1/2 the cost of a rebuilt one, and it is running 100% and delivers more stable voltage at all RPMs than the store-bought ones. You can buy good VRs for about $50/$60 with some shopping. Contacts are like $5.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yes, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Spray some furniture wax on it, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts.
If you battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can then fry it. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yes, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Spray some furniture wax on it, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts.
If you battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can then fry it. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
05-15-18, 09:26 PM
#5
Understood; when the ES alternator was bad 3 years ago, I was in the same situation and used a rebuilt from O'Reillys. Already replaced that one once since then (so make sure you purchase from whatever store has a lifetime warranty). My SUV had the bad VR about the same time. I rebuilt it myself for 1/2 the cost of a rebuilt one, and it is running 100% and delivers more stable voltage at all RPMs than the store-bought ones. You can buy good VRs for about $50/$60 with some shopping. Contacts are like $5.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yes, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Spray some furniture wax on it, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts.
If you battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can then fry it. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yes, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Spray some furniture wax on it, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts.
If you battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can then fry it. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
05-15-18, 09:29 PM
#6
Understood; when the ES alternator was bad 3 years ago, I was in the same situation and used a rebuilt from O'Reillys. Already replaced that one once since then (so make sure you purchase from whatever store has a lifetime warranty). My SUV had the bad VR about the same time. I rebuilt it myself for 1/2 the cost of a rebuilt one, and it is running 100% and delivers more stable voltage at all RPMs than the store-bought ones. You can buy good VRs for about $50/$60 with some shopping. Contacts are like $5.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yet, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Check the tray and clean up corrosion or electrolyte residue. Spray some furniture wax on the battery and clamp, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts and/or shorter battery life.
If your battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can and likely will then fry it before long. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yet, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Check the tray and clean up corrosion or electrolyte residue. Spray some furniture wax on the battery and clamp, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts and/or shorter battery life.
If your battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can and likely will then fry it before long. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
05-16-18, 04:09 AM
#7
Driver School Candidate
Thread Starter
Understood; when the ES alternator was bad 3 years ago, I was in the same situation and used a rebuilt from O'Reillys. Already replaced that one once since then (so make sure you purchase from whatever store has a lifetime warranty). My SUV had the bad VR about the same time. I rebuilt it myself for 1/2 the cost of a rebuilt one, and it is running 100% and delivers more stable voltage at all RPMs than the store-bought ones. You can buy good VRs for about $50/$60 with some shopping. Contacts are like $5.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yet, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Check the tray and clean up corrosion or electrolyte residue. Spray some furniture wax on the battery and clamp, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts and/or shorter battery life.
If your battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can and likely will then fry it before long. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
Now if you swap it yourself, be sure to remove the battery cables before you even touch the alternator. When you take off the connections, you can easily ground them and then you will instantly blow the 100 amp main fuse. It's secured underneath the fuse box and is a pain to replace. Do not put a wrench to the alternator with the battery cables in place. Better yet, take the battery out of the car so you can't have the cables flop back down against the posts; that can cause problems, too. When you have the battery free, clean the posts, top of the battery, and clamp. Check the tray and clean up corrosion or electrolyte residue. Spray some furniture wax on the battery and clamp, believe it or not but it prevents the electrolyte trails/crystals that can also lead to battery shorts and/or shorter battery life.
If your battery is very old or already known marginal, expect it to possibly go pretty soon after you put in a new alternator. The higher charging rate can and likely will then fry it before long. Very common. Better yet, put a multimeter on it one morning before work or after work before driving home (e.g., after it has sat 8 to 12 hours). Take a look at this chart:
https://www.energymatters.com.au/com...age-discharge/
If after sitting that long, if it is showing 12.2v or less, consider going ahead and replacing it before it strands you somewhere on the first really hot day in June. If it's above 50%, you should probably be good.
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