Big Medicine
Enthusiast
Where is this on the vehicle?
Voltage Regulator
- Thread starter Big Medicine
- Start date
Ron
Enthusiast
There is no independent regulator. Voltage regulation is handled by the ECM.
Big Medicine
Enthusiast
Ron,
I was throwing a code 4:6, high voltage detected in charging system. I pulled my alternator & took it to Autozone, and it seems to be pushing plenty of volts, almost 16. I took my battery for test, and it was unstable, so I bought a new one & the car quit throwing codes. Went on a test run & just as I was convinced I had found the problem, the car died in the middle of Highway 37. No power, no nothing. So, as in the past, I started jiggling with electrical appurtenances, tured on my headlights etc......but nothing. So I crawl out, pop the hood and happen to notice that my head lights had come on between getting out & popping the hood. I hop back in the car & all is normal......cranked right up & still not throwing codes. For anyone reading this who is tempted to reply that maybe I should check my battery connections or other, this has been done. My car was doing this kind of weird crap before I pulled the alternator & battery yesterday.
I'm looking for a root cause here, and I just can't figure it. I mean I'm almost to the point of pulling the entire wiring harness & combing every wire with a microscope. I feel strongly that whatever the root cause is may have ruined my battery, as it was 2 months old.
My car used to have a NOS system on it, and I have pulled everything related off of it. I think. Maybe I missed something? Hooked up wrong? I am pissed I can't drive the car this weekend & I am considering selling it.
I was throwing a code 4:6, high voltage detected in charging system. I pulled my alternator & took it to Autozone, and it seems to be pushing plenty of volts, almost 16. I took my battery for test, and it was unstable, so I bought a new one & the car quit throwing codes. Went on a test run & just as I was convinced I had found the problem, the car died in the middle of Highway 37. No power, no nothing. So, as in the past, I started jiggling with electrical appurtenances, tured on my headlights etc......but nothing. So I crawl out, pop the hood and happen to notice that my head lights had come on between getting out & popping the hood. I hop back in the car & all is normal......cranked right up & still not throwing codes. For anyone reading this who is tempted to reply that maybe I should check my battery connections or other, this has been done. My car was doing this kind of weird crap before I pulled the alternator & battery yesterday.
I'm looking for a root cause here, and I just can't figure it. I mean I'm almost to the point of pulling the entire wiring harness & combing every wire with a microscope. I feel strongly that whatever the root cause is may have ruined my battery, as it was 2 months old.
My car used to have a NOS system on it, and I have pulled everything related off of it. I think. Maybe I missed something? Hooked up wrong? I am pissed I can't drive the car this weekend & I am considering selling it.
HP
Enthusiast
Check your + battery lug terminal - it sounds like you have a bad connection,
which would explain your high alternator output and sudden loss of power.
which would explain your high alternator output and sudden loss of power.
SNKEBIT
Enthusiast
Isn't the voltage reg. internal in the alt.? seems to be a bit high on volts. too much voltage in the system screwin' things up? too much voltage mighta cooked your bat. 
if the reg. is ni the alt., might be chargin' too much, might need new alt
if the reg. is ni the alt., might be chargin' too much, might need new alt HP
Enthusiast
The PCM turns on/off the generator driver field - to regulate the alternator
charge that goes to the battery.
If the output circuit from the alternator to the + battery lug is shorted,
the PCM will continually activate the generator field - this is what triggers
the code (lack of driver off mode)
Of course there are other possibilities such as internal shorts inside the
alternator or bad PCM.
If you take the alternator out of the car - it will test ok
charge that goes to the battery.
If the output circuit from the alternator to the + battery lug is shorted,
the PCM will continually activate the generator field - this is what triggers
the code (lack of driver off mode)
Of course there are other possibilities such as internal shorts inside the
alternator or bad PCM.
If you take the alternator out of the car - it will test ok
SNKEBIT
Enthusiast
that's kinda the direction I was goin', alt. charging too much (stuck open). wouldn't a short in the main lead to the bat. cause a burnt wire or smoke or somethin' like that? thats a dead short 
Has to be bad alt. or pcm
Has to be bad alt. or pcmBig Medicine
Enthusiast
Quote by William:
"you have a open-circuit(possitive +)sorce which supplys voltage to the ALT-voltage regulator,the A/C compressor clutch,and coolant fan motor.The dash lamp is displayed because on start-up,with the key-on the lamp takes a ground from the Alt-regulator circuit,until you start the engine then the lamp goes out due to the regulator in return sends battory voltage back to the bulb on the same circuit.Which is how the light stays out when the engine is running or till there is a system fault in the charging-system.As one "other" pointed out on this post,check your fuseable links(****-fuses)also coolant fan motor connector(the three wirer connector may be melted together-due to a shorted fan motor)Check the harnnes also running back to the fan relay center,and the harnness to the Alt, for a short to ground,also the Alt it self may have a internal short.Wm"
I'll post a pic tomorrow, but my main fan relay looks like someone has been stick welding in there. This, obviously, is a contributing factor & explains why it only happens some of the time. There is a loop from the main relay to the fan speed relay, & I'm guessing I'm shorting everything out when a certain fan speed kicks in. Looking at the relay center from top, the bottom left relay's bottom connection, gray wire, is what's now an integral part of the plastic relay housing. Melted together solid.
My main concern now is what caused THAT to happen, or is the root cause elsewhere. I'll follow up by checking the fan wiring harness and connector. I inspected the alternator harness when I took the alternator off. I'm assuming I don't have a short in the alternator or it would have showed up on test?
Will folllow up tomorrow. Chuck Tator, I need some parts.
Thanks for all the input guys. HP, next time I pull through Little Rock on the way home, I owe you lunch.
"you have a open-circuit(possitive +)sorce which supplys voltage to the ALT-voltage regulator,the A/C compressor clutch,and coolant fan motor.The dash lamp is displayed because on start-up,with the key-on the lamp takes a ground from the Alt-regulator circuit,until you start the engine then the lamp goes out due to the regulator in return sends battory voltage back to the bulb on the same circuit.Which is how the light stays out when the engine is running or till there is a system fault in the charging-system.As one "other" pointed out on this post,check your fuseable links(****-fuses)also coolant fan motor connector(the three wirer connector may be melted together-due to a shorted fan motor)Check the harnnes also running back to the fan relay center,and the harnness to the Alt, for a short to ground,also the Alt it self may have a internal short.Wm"
I'll post a pic tomorrow, but my main fan relay looks like someone has been stick welding in there. This, obviously, is a contributing factor & explains why it only happens some of the time. There is a loop from the main relay to the fan speed relay, & I'm guessing I'm shorting everything out when a certain fan speed kicks in. Looking at the relay center from top, the bottom left relay's bottom connection, gray wire, is what's now an integral part of the plastic relay housing. Melted together solid.
My main concern now is what caused THAT to happen, or is the root cause elsewhere. I'll follow up by checking the fan wiring harness and connector. I inspected the alternator harness when I took the alternator off. I'm assuming I don't have a short in the alternator or it would have showed up on test?
Will folllow up tomorrow. Chuck Tator, I need some parts.
Thanks for all the input guys. HP, next time I pull through Little Rock on the way home, I owe you lunch.
HP
Enthusiast
I've always thought the wiring off the + battery jumper post was not well
thought out. All the critical wires to run the car, with their fusible links- are bundled together and wrapped. Mix that with the marginal
high amp fan relay wire, and you have a recipe for trouble. All it takes is
one wire to overheat, the wrapper retains the heat, and you end up with a
major meltdown.
thought out. All the critical wires to run the car, with their fusible links- are bundled together and wrapped. Mix that with the marginal
high amp fan relay wire, and you have a recipe for trouble. All it takes is
one wire to overheat, the wrapper retains the heat, and you end up with a
major meltdown.
Big Medicine
Enthusiast
DChan415
Enthusiast
Your battery cable makes a stop at the starter before it gets to the fusebox. Check the connection at the starter terminal. Thats where I had problems similar to yours before.
Big Medicine
Enthusiast
Thanks Danny.
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