Please help with diagnosis 3.2
08-22-2001, 03:29 AM
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Please help with diagnosis 3.2
I seem to be having a relatively simple problem with the alternator, but I was hoping that the members of Rennlist would help confirm that that is indeed the problem, and/or suggest any other possibilities. Here are the facts:
1. Although I unexpectedly found the battery dead a couple months back, the car was jumped and now starts fine and runs normally, even after very short drives and repeated starts.
2. The headlights are quite dim and their intensity varies with the engine speed.
3. The battery light comes on periodically.
4. Strangely enough, since the car was jump started and the battery light started coming on, the seatbelt light and buzzer come on randomly for a couple seconds several minutes into any trip even though I'm wearing the belt. Please note that the battery ligth seems to come on less frequently than that unexpected seat belt light.
5. The brake lights require a lot of pedal pressure before they will light, expecially when the headlights are on.
Should I replace the alternator right away? Please advise. Thank you very much in advance.
1. Although I unexpectedly found the battery dead a couple months back, the car was jumped and now starts fine and runs normally, even after very short drives and repeated starts.
2. The headlights are quite dim and their intensity varies with the engine speed.
3. The battery light comes on periodically.
4. Strangely enough, since the car was jump started and the battery light started coming on, the seatbelt light and buzzer come on randomly for a couple seconds several minutes into any trip even though I'm wearing the belt. Please note that the battery ligth seems to come on less frequently than that unexpected seat belt light.
5. The brake lights require a lot of pedal pressure before they will light, expecially when the headlights are on.
Should I replace the alternator right away? Please advise. Thank you very much in advance.
08-22-2001, 08:52 AM
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HB,
First you have to find out what is going on. Buy a VOM (volt ohm meter) that is digital, and you can find them at Radio Shack and others for $20 or less.
Open the motor hood and take the black cover off that you will find on the left back side of the motor compartment. Under there you will find two or three fuses. Clip one lead of the VOM on one of the fuses and the other lead to the body or motor where you get a good ground. Turn the VOM on and put it to 20V DC or so...
Your readings should be around 12.4-6 or so without the motor running, and at least 13.5 when running. It could go up to 14.5 or so on the high end but should not go below the 13 volt figure.
Once you know that the alternator is working or not then you can go from there. I had a bad regulator and at night the lights would go from normal to real bright. Turns out that the alternator was topping out at 16 volts! Bet the DME computer liked that!
You also might hook the VOM up inside the car so that you can watch the voltage while driving and putting various loads on the system. This is more realistic but I bet that you will find the alternator or regulator is going out.
Once there, then take the puppy out, and find a good overhaul shop in your area. Had mine overhauled for $75 or so compared to the $400 the dealer wanted... been running for almost a year now with no problems.
If you do not drive the car for long periods of time, I would look into trickle charging the battery to keep it topped up. The alternator is only so good and with many of us using the A/C these days there are times that the battery is never totally charged. The battery runs the car, the alternator only keeps it charged.
Hope this helps...
JA
First you have to find out what is going on. Buy a VOM (volt ohm meter) that is digital, and you can find them at Radio Shack and others for $20 or less.
Open the motor hood and take the black cover off that you will find on the left back side of the motor compartment. Under there you will find two or three fuses. Clip one lead of the VOM on one of the fuses and the other lead to the body or motor where you get a good ground. Turn the VOM on and put it to 20V DC or so...
Your readings should be around 12.4-6 or so without the motor running, and at least 13.5 when running. It could go up to 14.5 or so on the high end but should not go below the 13 volt figure.
Once you know that the alternator is working or not then you can go from there. I had a bad regulator and at night the lights would go from normal to real bright. Turns out that the alternator was topping out at 16 volts! Bet the DME computer liked that!
You also might hook the VOM up inside the car so that you can watch the voltage while driving and putting various loads on the system. This is more realistic but I bet that you will find the alternator or regulator is going out.
Once there, then take the puppy out, and find a good overhaul shop in your area. Had mine overhauled for $75 or so compared to the $400 the dealer wanted... been running for almost a year now with no problems.
If you do not drive the car for long periods of time, I would look into trickle charging the battery to keep it topped up. The alternator is only so good and with many of us using the A/C these days there are times that the battery is never totally charged. The battery runs the car, the alternator only keeps it charged.
Hope this helps...
JA
08-22-2001, 11:33 AM
#3
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Just a thought, HB...
While driving, did you ever smell a nasty, sulfur smell coming from within the car? If you did, it's not a manifestation of an automotive Lucifer, but a cooked battery.
Caused by a failed voltage regulator, the cooked battery can mess up your trunk with sprayed acid. Not good.
And one other thing that may relate to your car's problems....check the battery ground point in the trunk. It's right near the battery...just follow the negative lead. This grounding stud is frequently corroded and should be should cleaned up. Use a bit of "Never-Seez" grease on the connections for good measure.
While driving, did you ever smell a nasty, sulfur smell coming from within the car? If you did, it's not a manifestation of an automotive Lucifer, but a cooked battery.
Caused by a failed voltage regulator, the cooked battery can mess up your trunk with sprayed acid. Not good.
And one other thing that may relate to your car's problems....check the battery ground point in the trunk. It's right near the battery...just follow the negative lead. This grounding stud is frequently corroded and should be should cleaned up. Use a bit of "Never-Seez" grease on the connections for good measure.
08-22-2001, 03:11 PM
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HB--the foregoing suggestions are excellent and will probably prove to be correct. However I'd suggest one add'l thing to check. The fact that you're getting random buzzers and lites are indications of back circuits and they are usually caused by BAD ground connections. When the current can't reach ground thru it's normal path--it'll branch off thru other devices seeking a path to ground--erratically powering those units along the way. Check your battery to chassis ground carefully as well as the tranny to chassis ground. NOT JUST VISUALLY!! SHINE them up, make sure they're tight, smear on some dielectric grease. You'll find many little gremlins will disappear with clean battery terminals and electrically sound grounds. 
08-22-2001, 03:19 PM
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It's most likely the voltage regulator that's causing the seat belt light to come on. This happens when the voltage is too high.
If your driving at night you might notice the head lights get bright the instant the seatbelt light comes on.
The brake light not coming on until hard braking is probably an unrelated problem, most likely the switch on the master cylinder.
Tim
If your driving at night you might notice the head lights get bright the instant the seatbelt light comes on.
The brake light not coming on until hard braking is probably an unrelated problem, most likely the switch on the master cylinder.
Tim
08-22-2001, 05:15 PM
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Thanks everybody! Your suggestions are very helpful.
Tim,
Thank you for linking the seat belt light to a voltage problem caused by the regulator. Do you think I'm at risk of being stranded? Is this a problem that should be taken care of immediately?
Tim,
Thank you for linking the seat belt light to a voltage problem caused by the regulator. Do you think I'm at risk of being stranded? Is this a problem that should be taken care of immediately?
08-23-2001, 07:59 AM
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Hi. Best thing you can do is keep an eye on the little voltmeter you got and observe the warning lamp for the alt. Even if you turn the key on, before you start the motor, no warning lamp indicates a problem.
Have a look at these as a replacement, they are NEW.
www.aasesales.com
Saint
Have a look at these as a replacement, they are NEW.
www.aasesales.com
Saint
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08-23-2001, 10:34 PM
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HB,
George brings up some very good points, but you need to get a volt meter on the system to tell what you are working with in the first place. You could be low on voltage or high, neither of which is good.
Check the grounds, as one of them being disconnected or dirty will play havoc with any cars system. As George says, make sure they are a good clean contact. Your cars system is even more of a problem with the DME fuel injection computer.
It cannot stand the abuse a normal car with carbs or CIS could, so pls check the above items before driving the car too much. Being stranded is a very real option if you over-volt the system and either the DME relay or computer takes a dump. One is less than $100, the other is around $1000, so neither one is cheap.
Prevention is cheaper...
Joe
George brings up some very good points, but you need to get a volt meter on the system to tell what you are working with in the first place. You could be low on voltage or high, neither of which is good.
Check the grounds, as one of them being disconnected or dirty will play havoc with any cars system. As George says, make sure they are a good clean contact. Your cars system is even more of a problem with the DME fuel injection computer.
It cannot stand the abuse a normal car with carbs or CIS could, so pls check the above items before driving the car too much. Being stranded is a very real option if you over-volt the system and either the DME relay or computer takes a dump. One is less than $100, the other is around $1000, so neither one is cheap.
Prevention is cheaper...
Joe