[jrcorsey]

I have a 2002 New Beetle TDI Sedan, 1.8T engine. I bought it used about a year ago. Love this car, except....

At first, I had erratic, frequent dead batteries. Loooong story short, I replaced the ignition switch and harness clip, as described in this post:

VWVortex.com - **Ignition Switch Replacement DIY**

And then I replaced the battery, which was killed by the repeated discharges. At that point, the incidence of dead battery dropped to around 10%, and 0% if no dash controls were used. That was enough to make the car my wife's daily driver.

Later, I found the trigger - the battery only dies if the radio has been used. After the radio has been used, even if it was turned off before the car, the battery will die within a day. It starts immediately with a jump, but will die again if it sits for around 10 hours. After 2 or 3 jumps, the drain disappears and the battery does not die again. After that, as long as the radio is not used, the battery never dies.

I suspect the amp from my reading on this thread (monsoon amp and radio, factory installed, no obvious work performed). I'm wondering if anyone has troubleshooting suggestions, or knows of another piece of equipment that might be failing only when the radio is on. How to rule out or verify the amp theory would be especially welcome. Thanks for any help!

 

[pencilneck]

Have you tried setting up a parasitic draw test?

How To Perform a Parasitic Draw Test - YouTube

 

[Greg-S]

Usually I'm just lurking around but after reading this I felt I better respond. Shortly after my wife got her 2003 last year we started to experience an ocassional dead battery. When I determined it was a draw and hooked up my multimeter in line with battey and found a 2 plus amp draw. I then started pulling fuses till it went away. When we pulled the radio fuse bamm draw gone. If she only put that fuse in when she drove car and took it out when done the battery never discharged, but if we left it in battery would go dead. When the fuse was in the amp never felt warm so I figured it wasnt that. Found a new VW monsoon on Ebay and it totally solved our problem. I know I left out some details or how I tested so if yo have more questions just ask.

Greg

 

[Oh Randi]

Heh. I remember this issue with mine. Car would be dead within a day, but only when the temperature was above 70. Spent 2 years trying to figure out what it was, and eventually figured out it was the monsoon amp I didn't know I had. But in my case, I'm pretty sure the aftermarket speakers had something to do with it. But in any case, the amp wasn't shutting off and was drawing close to 2 amps. So I ripped that sucker out, cut the plug off, wired it back up and never looked back.

Still not sure why it only killed the car in warm weather... I get a headache and get slightly agitated thinking about it. eliminating the amp solved the problem though. Crazy monsoon amps.

 

[jrcorsey]

Pencilneck, i have set up a parasitic draw test, but the only way to isolate radio circuit components is to access the wiring harness under the dash, with the exception of the amp, which could be unplugged. Removing the dash is rather time consuming, so I was hoping someone who knew about the circuit in question could advise me on best ways to isolate the components.

Also, since I don't have a Bentley and don't know how the amp is wired, I wouldn't really know whether the drain was in the amp or the disconnected circuit. Also, the only condition under which I can replicate the draw is to use the radio, but I read that disconnecting the amp disables this radio, so that's also inconclusive.

I do appreciate your suggestion, I agree that it's the right thing to do in principle. I'm just looking for ideas how to go about it.

 

[jrcorsey]

Greg-S, did you replace the Monsoon amp or the radio? And how did you know to replace it, or was it a lucky guess? If you don't want to post that it was just lucky, you can PM me. Thanks!

 

[jrcorsey]

Oh Randi, it's always over 70 in Los Angeles, so I got off easy, I guess. If you and George want to drive out this way, we can reminisce about troubleshooting gremlins over some of my patented 'headache medicine'. I'll whip up something special for George, too... a sort of a veggie smoothie. It's very California.

BTW, did you replace the amp and stereo at the same time, or in what order? And did you have any issues wiring the Alpine? I've seen vague, ominous murmurs about proprietary wiring that never matches 'standard' pin outs, but no real specifics yet.

 

[Oh Randi]

Oh Randi, it's always over 70 in Los Angeles, so I got off easy, I guess. If you and George want to drive out this way, we can reminisce about troubleshooting gremlins over some of my patented 'headache medicine'. I'll whip up something special for George, too... a sort of a veggie smoothie. It's very California.

BTW, did you replace the amp and stereo at the same time, or in what order? And did you have any issues wiring the Alpine? I've seen vague, ominous murmurs about proprietary wiring that never matches 'standard' pin outs, but no real specifics yet.

From what I remember, I first did the alpine head unit didn't notice any issues. Shortly after did the kicker speakers. But between the motor swap that happened in between I don't remember exactly when the problem reared its ugly head. I didn't have any issues wiring it up, as the previous one that came with the car was a JVC and it came with the adapting harness so no cutting of the factory plug was needed. I didn't know I even had an amp, as I didn't see a power wire for it. Apparently there is no power wire, the amp is voltage sensing or something to that nature, correct me if I'm wrong. I did notice intermittently after the car was shut off I could hear a faint popping/buzzing from a rear speaker. I guess the amp would sense that and stay on? In any case, I cut the amp out and am now ampless. And haven't had an issue since.

I personally love my alpine. I am still unsure if it was causing the issues with the amp, it might have, considering the JVC didn't cause the amp to stay on. But it doesn't matter now, I wanted the factory amp gone. It was causing my kicker speakers to sound like crap. The amp was sending woofer-only to my coax's.. Not cool. My tweeters were blown anyhow. Ii just unpugged em.

Car doesn't drain overnight anymore, so I've lost interest in further pursuing the matter.


And btw, your first paragraph killed me! Haha I'll definitely pop in for a visit if I ever leave the wretched state of Oklahoma.

 

[jrcorsey]

Back to the drawing board....

So I finally got around to unplugging my Monsoon amp, and learned a couple of things.

First: with the amp unplugged, the radio will turn on, but will not make sounds.

Second: the amp is not the culprit.

The car worked fine for 2 days of driving with the amp unplugged and the radio turned on. On the third day, the car started in the morning but was dead by 8:30 pm. Jumped it and drove home with no radio. Car started on the morning of the fourth day, but was dead again on the evening of the fourth day. Not sure if the radio was turned on that morning or no.

In case it's not clear, the radio is always turned off before the car is turned off.

Days 5 and 6, no problem morning or evening.

So, NB troubleshooters, what do you suggest next? Please, please let it be something that doesn't require removing the dashboard.

Thanks!

 

[Greg-S]

Pull that radio fuse and see if problem goes away. Thats how I was sure it was that circiut. You can even put it in if you want to listen to radio while you drive, but pull it again when you shut it off.

 

[jrcorsey]

Solved at last!

So, following Greg-S, I pulled every fuse I could live without, and the car ran fine for about six months.

Then the battery began to run down again. I bought a jump pack and jump started it every morning and night for about a year.

Finally, that killed the battery dead, and when I went to buy a new one, I found the ultimate culprit; a regular size battery.

Someone had installed a smaller battery than the ridiculous truck battery VW specifies. The parts store I went to had the smaller one listed as an alternate for the car, but I decided to splurge for the full size.

I then replaced all the fuses, and voila, no more gremlins.

It's been over a year. At first I didn't post because I wasn't sure I'd fixed it; later I wasn't visiting NB.org because I didn't have car trouble.

Just thought I'd provide closure in case some poor soul has a similar issue in the future. Thanks all for your help!

 

[fjheller]

I have a 2002 New Beetle TDI Sedan, 1.8T engine. I bought it used about a year ago. Love this car, except....

At first, I had erratic, frequent dead batteries. Loooong story short, I replaced the ignition switch and harness clip, as described in this post:

VWVortex.com - **Ignition Switch Replacement DIY**

And then I replaced the battery, which was killed by the repeated discharges. At that point, the incidence of dead battery dropped to around 10%, and 0% if no dash controls were used. That was enough to make the car my wife's daily driver.

Later, I found the trigger - the battery only dies if the radio has been used. After the radio has been used, even if it was turned off before the car, the battery will die within a day. It starts immediately with a jump, but will die again if it sits for around 10 hours. After 2 or 3 jumps, the drain disappears and the battery does not die again. After that, as long as the radio is not used, the battery never dies.

I suspect the amp from my reading on this thread (monsoon amp and radio, factory installed, no obvious work performed). I'm wondering if anyone has troubleshooting suggestions, or knows of another piece of equipment that might be failing only when the radio is on. How to rule out or verify the amp theory would be especially welcome. Thanks for any help!

AHAH!.....same problem. got a fault reading from recharger and no recharging. Yesterday, did a 2 amp. charge and got it partially charged. But the radio bleed and draw is perplexing....installed a new Monsoon radio.

Sometimes turn on key and nothing. partial charge and key produces partial display. Will have alternator and ignition checked out.

Love the car for riding around, but this problem is a P.I.A.

 

[XavierNusum]

typically this is only caused by aftermarket radios with monsoon amplifiers, but I have heard of it with the factory radios as well. Whats happening is the "signal" from the radio to turn on the amp isn't there so the amp is staying on. Try checking voltage at the amp with everything closed (trunk latched) and after interior lights have turned off. If you still get power you know the amp is draining the battery. There is a YT video that shows how to install a relay to control the amp to turn on/off with a remote wire.

https://www.youtube.com/watch?v=nYXAExiaRgg

 

[cderanger1970]

how do you get to the amp to test for voltage if the trunk is latched? i have the factory monsoon radio and am constantly having to charge my daughter's battery. i want to install a relay. i have found the constant 12 v wire but am not sure how to determine which other wire needs to be connected to the relay as mine is not an aftermarket radio.

 

[XavierNusum]

To do the test you would want to take a screw driver or similar and force the latch closed with the hatch open.

Before that remove the plastic covers in the trunk closest to the taillights to give you access to the amp. There will be a pretty good sized red power wires that splits into 2 or 3 smaller gauge wires which, if I remember correctly, all go to the amp. I think I have some pics, I’ll try to get those posted. Once you’ve closed all the doors, hatch manually latched and the courtesy lights go out, measure voltage at any point where the red wires connect to the amp. Chances are you’ll see 12-13v if this is the source of your drain.

You will need a 12v signal to turn to close the relay which may take a little creativity seeing that you still have the factory head unit installed.

Found the pics, here they are!