Code P1600 Supple voltage too low HELP

**stormscr3** · 10-18-2009 05:12 PM

Was driving around running errands and my battery light came on signaling my voltage was low. Look at the dial and it says my volts are down to roughly 10 when it usually reads 14v on average. I was like ah shit so I start driving toward home and all the lights in the world came on in my dash and my bezel lights became really dim. I have HID's and they were fine but everything else dimmed. When I pulled in and parked back at home the volts read 7. I'm thinking bad connection, battery is starting to go or my alternator (not in that order). Is there an easy fix i'm missing or is this one of the things I listed.

I have an OBDII Scanner and it spit out P1600 and for VW it means supply voltage is too low. Thanks Guys I really need some help.

**97a41.8t** · 10-18-2009 05:21 PM

Sounds like the alternator at fault. Get a battery charger and charge the battery back up or you'll be getting a new battery too :p

Unfortunately, I don't think there is an alternator fuse and the voltage regulator is built internally to the alternator. Get a steel brush and brush those terminals and maybe some battery cleaner and dielectric grease. But I think its time for an alternator upgrade

**stormscr3** · 10-18-2009 05:23 PM

Any place in particular you recommend? I'm about to start on ebay and our classifieds section.

**GR-RALLYE** · 10-18-2009 05:32 PM

Originally Posted by stormscr3

Any place in particular you recommend? I'm about to start on ebay and our classifieds section.

ap-specialtes or local junk yard is your best bet IMO

**97a41.8t** · 10-18-2009 05:34 PM

Well, I would just take it out and go to your local parts store and get a rebuilt one or similar.

Hard to say on anything used how long it will last....

**walky_talky20** · 10-18-2009 05:40 PM

How many miles are on the car? If you've got over 100k miles, the brushes in the alternator have probably failed. If it were mine I'd just replace the brushes. I've put brushes in the Valeo alternators, it is pretty easy. I'm not sure about the Bosch alternators. I think the brushes were about $5. I'll have to do a write-up on it the next time I rebuild one. I do know you can buy the voltage regulator/brush assembly from Audi, but it is over $100 AFAIK.

If you know its just the brushes, you might try calling around to find a local place that would replace the brushes for you. Or if you can find a used alternator with low miles, that works too. Just some ideas. The entire problem could be something else, too. So make sure you properly diagnose before just buying stuff.

**stormscr3** · 10-18-2009 06:57 PM

Thanks Walky Talky I'm gonna diagnose it tomorrow, it's been so cold these past few days. My car has 176,000 on it and almost positive it's the original Alternator lol, so I think that idea could be very plausible.

**stormscr3** · 10-27-2009 11:48 AM

I've searched but without many results. I'm guessing the replacement of the alternator involves removing front bumper, ac condenser, radiator, then surrounding belts. I'm gonna replace all the drive belts but does anyone have a DIY?

**TverRus69** · 10-27-2009 10:08 PM

Sorry for stating the obvious but have you made sure that the alt belt is still there?

**Demon** · 10-27-2009 11:11 PM

i changed my both belt's w/o taking front bumper off. It was tight and didn't take front bumper off.If its Alt Should be able sneak it out by just removing front Rad hose above the Alt or try sneaking it out 1st.No bleeding the coolant system that why.Good luck and god speed!

O_o you have 2.8 V6 Good luck w/ alt but belt is still easy to do

**99blueb5** · 10-28-2009 07:45 AM

before you buy another one go to schucks or autozone or even sears and take you alternator and get it tested for FREE, they will tellyou the results and everything, if it passes check ALLLL grounds and positive battery cables for a good conection, i just went through this mess and it ended up being a bad positive battery cable that came from the starter to the alternator

**stormscr3** · 10-29-2009 12:21 PM

I'll try everything you guys just told me I really appreciate it ... i'll post results

**Armenian** · 05-14-2011 05:41 PM

Hey, i was wondering what fixed your issue, i have a 99 a4 quattro 2.8 and i have the P1600 code which is saying voltage too low . I guess i will start by checking for the positive wire to the starter then go from there anything else i should look into ?

Thanks