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VW Jetta Electrical Problems

305 messages,  Last post on May 16, 2013 at 2:17 PM

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Messages Page 25 of 31

#241 of 305 2004 Jetta GLS (Electrical Problems) by vjimenez

Oct 25, 2011 (11:25 am)

So, I bought a 2004 VW Jetta GLS with 103K mi on it. NO warranty or anything. So, I regularly do the tuneups, check tires, etc. I do my best to keep my baby clean and well maintained. I now have around 115K miles on it. But, just recently my instrument cluster says one of my doors are open. I close all the doors, the trunk, and even the hood of the car. And it will go away but after driving for a little all my lights come on and it says one of the doors is open. I still have the same manufacturer battery. But, I never had any problems starting the car. Any suggestions you guys? Or has this happened to any of you guys? Thanks

#242 of 305 Re: 2004 Jetta GLS (Electrical Problems) [vjimenez] by bpeebles

Oct 28, 2011 (5:55 pm)

Replying to: vjimenez (Oct 25, 2011 11:25 am)
The electrical switches for the doors are contained within the latch mechanism inside each door. I believe there are 3 micro-switches per door. The onboard computer can tell if each door is open/closed/locked....etc
 
If any one of the 3 switches goes bad, then the computer can get confused. Sometimes, the alarm-system starts to act up...Other times, the auto-locking system gets wonky.
 
In any case, it is not unheard of for this to happen. There are several websites which have step-by-step instructions to pull the door apart. Or you can take your car to a shop for repair.

#243 of 305 low voltage by eros1

Oct 30, 2011 (11:15 pm)

92,diesel,changed alternater and battery,cleaned all terminals,checked fuses and relays,still getting low voltage 12.29,also tach does not work,it will flicker but then goes to 0,

#244 of 305 Re: low voltage [eros1] by bpeebles

Oct 31, 2011 (4:37 pm)

Replying to: eros1 (Oct 30, 2011 11:15 pm)
You made some statements... but did not ask any questions. I will assume you meant to ask how to troubleshoot an alternator.
 
It is pretty simple with a voltmeter and some basic electronics knowledge.
 
The voltage-regulator is built-in to the alternator. It is supposed to regulate the voltage at about 14.8 volts while the engine is running.
 
Your 12.3 volts sure sounds as if the alternator is not even in the circuit. Are you *certain* that the fuseable-link between the alternator and the battery is not burned out?
 
hint: measure voltage-drop between alternator output and battery+. There should never be more than 500mV across this wire.
 
Also verify ALL of the ground connections under the hood. Make certain that all measurements from battery- to all other grounds is never more than 300mV.

#245 of 305 2005 Jetta Flickering lights and occasional stall by owenstc

Nov 03, 2011 (6:29 am)

So my 2005 Jetta TDI is in the dealership today after I had to tow it yesterday. For the last 3-4 weeks, I've been experiencing constant "flickering" of the headlights and internal lights while the car is on. Yesterday, the car seemed to be hesitating while accelerating. After about 45 minutes of driving, the engine completely shut off while it was rolling and all power lost temporarily. The starter still cranks, and all the internal electric were still operating after the stall, but the engine would NOT fire again, for at least an 45 minutes after the stall. I had a tow truck tow the car to the dealership and it was left on the lot. Later yesterday afternoon, I get a call from the dealership and they say the car is starting and running fine, no issues at all.
 
I had originally figured the Alternator could be at fault, but the dealership says the alternator was "fine". The battery is brand new and cranks hard. But I keep thinking and mentioning to the dealership the flickering light issues. I'm worried I have an electrical issue, obviously, but don't know what to do or to ask the dealer to do for me. They seem to want to give the car back to me, but I'm worried about taking the car back without getting answers to why the car wouldn't start for an hour yesterday. All I'm hearing from them is "we can't recreate the problem".
 
Can any electrical experts on this page give me some suggestions as to what you'd do in my situation? Car at dealer, running but with symptoms, and they are not giving me a clear picture of what the next step should be.
 
Thanks for any assistance.

#246 of 305 Re: 2005 Jetta Flickering lights and occasional stall [owenstc] by bpeebles

Nov 03, 2011 (3:43 pm)

Replying to: owenstc (Nov 03, 2011 6:29 am)
Your dealership must be boneheads.... most automobile electrical systems can be easily troubleshot with a voltmeter.... heck, it is simply a 12 volt DC system.
 
With that said, I am not sure what you mean by the term "flickering" -- are you suggesting that all the lights are TOTALLY going out and back on... or are they simply getting dimmer/brighter ?
 
Does it happen with the engine OFF -or- ON?
Sittiing still -or- idling?
When reving engine?
when going over bumps?
When accellerating?
When braking?
....etc, I could ask 10 more questions to help isolate your issue.
 
If your dealership did not ask these questions, they have no clue what they are dealing with in the first place.
 
Also, VWs have voltage monitors all over the system built right in. One could hookup a computer to your car and DRIVE it while logging various key voltages in realtime.
 
Again, if your dealership has not done any of this - they are poorly-trained and not worth paying.

#247 of 305 Re: 2005 Jetta Flickering lights and occasional stall [owenstc] by auto06

Nov 04, 2011 (11:29 am)

Replying to: owenstc (Nov 03, 2011 6:29 am)
I've been servicing my wifes 2004 GL 2.0 since new and been driving it (75K)since we got a newer car for her. She complained that the car would not start sometimes; but wait 45m- 1hr later no problems. This happened to me one sunday after driving 35 mi, stopping for 2 hrs and "no start". This happened actually twice. 1st time tried everything remove the inlet hose by throttle, checked elec throttle plate, checked battery and fuses. all was okay waited for 2 hrs, started with no problems. I changed the fuel filter (1st time since new) 2nd time same schedule and location "no start". This time I saw someone on YouTube unpluged the fuel pump fuse (by the driver door) and turn on ignition switch then reinserted the fuse. and re-started the car. I tried it; and it worked! So that told me this is related to the elec wiring! The third time; I notice that when I turn the ignition switch on I can hear the fuel pump come on "normal" #1 clue; when it will not start - no fuel pump noise = no power at the pump. I also notice the door light stopped coming on at night when I open the door (note if you use the remote entry key the light will come on), test this by leaving door open and testing the door switch #2 clue. I've looked at "ALL DATA" at the local library and notice that there's a special Fuel pump relay under the driver foot well, under the steering wheel area. VW wanted $400.00 to fix the door/interior light; which might be associated with this problem. I'm going to spend $45.00 on the fuel pump relay. Wish me luck. Next prob is fixing the traction control light- Dealer wants $600 to fix steering wheel sensor.

#248 of 305 Re: Interior Electrical Stops Working After Headlight Use [kes4] by kes4

Nov 04, 2011 (12:01 pm)

Replying to: kes4 (Oct 05, 2011 4:58 pm)
Update on my jetta electrical issues. Mechaninc found that battery was running mostly at 12.8 volts and should be 14.4. He removed our aftermarket radio and cleaned and tightened all connections- there was corrosion on wires under battery tray. After that, he found the battery was running at 14 which was much better. However, it still dips down slightly when car idles or decelerates. Investigation on web has shown that the ABS/traction control lights are sensitive to voltage. This was 3 weeks ago. All electrical problems have ceased. However, we have gotten the ABS/traction lights 3 times while idling. The mechanic suggested that I may want to replace the alternator if the abs/traction control gets worse. He suspects that will prevent the voltage from going down when idling or decelerating.

#249 of 305 Re: Interior Electrical Stops Working After Headlight Use [kes4] by bpeebles

Nov 04, 2011 (5:17 pm)

Replying to: kes4 (Nov 04, 2011 12:01 pm)
Have you tried removing/cleaning all ground connections you can find?
 
Additionally, the connections to the voltage-regulator should be removed/cleaned.
 
Also, I am formally trained in electronics. When someone says they measured xxx Volts, this is NOT a satisfactory statement. First of all... what are you using as your ground-reference point? (it may make a HUGE difference)
 
Here is a typical example of what I have found on several automotive electrical systems...
 
SYMPTOM: Voltage measured across battery terminals is less that 14 volts.
HOWEVER: The voltage regulator *thinks* it is properly regulating at 14.8 volts.
REAL PROBLEM: The negative wire between battery - and voltage-regulator has over 2 volts of 'drop' across it - hence, the 'reference point' for the regulator is off by 2 volts.... this is the reason the voltage at the battery is off by 2 volts.
 
BOTTOM LINE: if the alternator is putting out ANY voltage, a 'low voltage across battery' problem is likely NOT an issue with the alternator itself. Instead, consider troubleshooting the VOLTAGE REGULATOR. (which happens to be screwed into the rear of the alternator.)
 
Why is this? Because the voltage-regulator is really controlling the alternator and telling the alternator what voltage to put out. If the voltage is wrong, it is the REGULATOR which is likely the problem. (or connections to it!)
 
In rare cases, one of the rectifier diodes inside the alternator may fail... I believe these too are replaceable without having to pay for a new alternator.

Messages Page 25 of 31

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