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Alternator seized, car has full power

9K views 146 replies 9 participants last post by  Digmenow 
#1 ·
Ok this might be alittle confusing but i will do my best to explain what my problem is. Here we go!! my 2001 S430 was sitting for awhile and battery ended up dying on me so i replaced it but what happened was from all the summer heat the idler pulley melted to the serp belt and the idler pulley broke and serp belt came flying off. Now i replaced the idler pulley which was very cheap and also a new serp belt, when i went to start the car there was a slight turn over but come to find out the alternator was seized and of course wouldn't start. I did have the car started without the belt on so i took the belt back off to see if i could get it to start again but i seemed to have maybe blown a fuse somewhere which i have no idea if thats the case or not. The car still has full power and all the lights work from the new battery. Did i blow a fuse or is it something else? Plz help cuz i had the car sold until it wouldn't start or even turn over.
 
#2 ·
How do you know the alternator was seized ? It does not make sense both your pulley and alternator seized at the same time

and the car should run just fine even with no alternator (it will just drain the battery )

The main fuses are located under the pasenger side floor
 
#3 ·
Seems to me the alternator was seized and that's what caused the belt disaster. Is that your opinion as well, or do you think the alternator seized while it sat after the belt flew off?

Unless you're living in hell, there's not enough heat on the planet to melt the idler pulley, the belt did that

Alternator isn't needed to start the car. Volts and amps are. How long did the battery sit, connected to the car before you tried to start it? Days, weeks? parasitic power drain would be enough to wipe out the cranking amps on the battery if it sat long enough.

Oh, and every time you turn on the lights, etc, to make sure the battery has enough juice, you rob it of some of that precious power.

Suggest you CAREFULLY have someone help you try and jump start the car. If it starts with the help of a fully charged battery, then you've diagnosed the problem. Next step would be to get the alternator rebuilt or replace it. But first, figure out if you have enough juice to start the car.

If a jump doesn't help, then you have a more serious problem elsewhere, but there usually is a relay to the starter, which may be a problem as well.

I'm 99% sure it's a voltage/amperage issue coming from your battery.

D
 
#4 ·
The car was sitting for mths but i jump started it with the old battery but the idler pulley broke somehow. Maybe the seized alternator cause the belt to slip off. I replaced the battery first then the car started no problem without the belt on. Then i replaced the idler pulley and serp belt without knowing the alt was seized, so it tried to turn over slightly but made a clicking noise then i got nothing. I removed the serp belt and tried to turn the alt pulley and it wouldn't spin so that leads me to believe its seized. I tried starting the car without the belt on and it wouldn't start anymore but i still have full power to all the lights as its a brand new battery. could it be a starter relay, a fuse, i don't know that what i need help figuring out.
 
#8 ·
Check if you have power at the starter motor main cable(the thick one), if not you have blown the prefuse under the carpet. If you have power at the starter motor let us know.


Dean
 
#10 ·
Sorry but i don't even know what side the starter is on on this car and are you talking about the prefuse location is under the passenger side footwell under the steel square cover. My apologies but i know nothing about these cars except i love driving them...lol Do you by chance have any illustrations of both starter location and prefuse location?
 
#11 ·
The starter motor is on the right hand side of the motor, and yes the prefuses under the carpet. Yes the prefuses are X4/10.

Dean
 

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#13 ·
Ok guys, i replaced the alternator and still no luck. I have full power since there is a new battery and alternator but still won't even turn over. I must have shorted a fuse somewhere when trying to start it originally when the alternator was seized. Any suggestions on what fuse or fuses may have been affected or what should i look for to resolve this problem so i can sell the damn thing?
 
#16 ·
Ok I know where they both are but haven't had a chance to look yet but if the one at the footwell passenger(JUNCTION FUSE TERMINAL) how do i know if its no good same with the relay. How do i test them? Just replace or is there a specific test you can run?
 
#17 ·
With a multimeter check for continuity accross the fuses or with a test light check for voltage on both sides. For the relay it is best to listen for a click you can hold a finger on it and someone else turn the key or swap with a different relay.
 
#21 ·
Possible that you toasted the starter solenoid.

As I recall, you can bridge over the solenoid on some cars to bypass it, to see if that's the problem. Google it for details.

Also, do the ancillary items light up when you turn the key? Dash indicators, turn signals work, etc?

D
 
#23 ·
All the lights are working as a have put a new battery in and alternator was rebuilt but car doesn't even turn over but the relay seems to be fine because i had a friend put their thimb on it and it clicks. I haven't had a chance to get to the starter because the car is so low that i can't get the floor jack under it to lift it up. The prefuses look fine but i haven't checked the continuity on any of them yet. Hopefully i will be able to tackle it since i'll be off work all next week but i'll be honest i have no idea what i'm doing...lol
 
#22 ·
Have you checked the prefuses and the main power cable at the starter yet???
What were the results???
We don't type these questions out for the fun of it, if you want help then check what is asked of you to check then reply with the results. If you can't do the simple things asked of you we can't help you.
 
#25 ·
Could also hotwire the starter with jumper cables. I don't necessarily recommend that, but it sure as hell will get to the bottom of, "Is it the starter, or something else."

Use jumper cables, go straight to the hot, ground should already be in place, but if needed, run the second cable to the neg terminal on the battery. GROUND IT FIRST.

I DO NOT RECOMMEND THIS AS THE FIRST THING TO TRY.

Prefuse, solenoid, then this as a last resort.

D
 
#26 ·
Back to basics...

What we need is a very precise, very detailed description of what happens and doesn't happen when you try to start the car. "Nothing" is not an acceptable answer!

Are the dash lights on with the switch in position 1 (first clockwise notch)?

Are they on in position 2?

Do accessories (radio, HVAC, etc.) work in position 2?

If you listen carefully, can you hear any faint clicks (or anything else) when you turn to position 3?

Can you move the gearshift lever under any condition?

If the interior lights are on, do they dim or go out in position 3?

The more that you tell us, the more likely that we can help you...
 
#27 ·
Yes the dash lights work in both position 1 and 2, all the accessories work as well.
I don't hear anything while turning to position 3.
When the problem 1st occurred i was able to move the gearshifter with the key in position 2 but now it won't move out of gear.
None of the lights dim or go out in position 3.
what i have done so far to the vehicle:
1: New battery
2:rebuilt alternator
3: New serpentine belt and idler pulley

Car has full electrical power, key fob works fine when it comes to unlocking and locking doors.
 
#29 ·
As the accessories all work you don't need to check the rear prefuses. What does the dash display for the gear?
You check the prefuse with a multimeter or a test light. The multimeter is the better option, use it to test the main power cable at the starter as well.
 
#30 ·
If the car is not in park, it's not gonna start. A little hard to tell, but last post indicates car is stuck "in gear" Is it in PARK, or Drive, or what? It's sure as hell not gonna start if the ignition interlock isn't in "P"

Have you tried wiggling the gear selector to make sure it's all the way in park?

Again, sounds dumb, but given all the other evidence, I'm starting to lean towards dumb. :)

D
 
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