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(This is my first question here so let me know if it is off-topic or not enough info provided, or otherwise inappropriate for the forum and I will delete it)

I have a 2001 VW Golf which has started exhibiting a disturbing electrical problem: I turn the key and just hear the starter "click". The dashboard clock gets reset to "12:00". There is still power but not enough to start the car.

If I wait and/or put the clutch in and shift gears, it will usually start as normal, with no indication of weak battery or other problem. It will then run fine for a couple of days and then the problem happens again. However, this is not predictable (shifting gears doesn't always "fix" it, etc) so it is unclear what the problem is.

  • the battery is @ a year old
  • the car was recently checked out for a power steering noise (whining). They topped off the transmission fluid

I don't have a mechanic I have confidence in and I have heard that electrical problems like this are notoriously hard to diagnose. Consequently I am thinking of taking it to a VW dealer for service on the hope that they will be more familiar with an issue like this.

It doesn't seem like a weak battery problem. I looked at the battery cables and they seem tight.

Is there anything else which would cause an intermittent failure like this? The car has had no collisions or other incidents which might have damaged the electrical wiring, etc.

Not looking for a "diagnosis" per se but hoping to become more informed so I can talk to the mechanics and not end up on some expensive "replace this and that" joy ride.


Adding a little more information:

So today the issue occurred while I was driving: the car stalled and would not restart. Strange electrical behavior on the dashboard: indicator lights on, lights off. Previously this has only occurred a few times when starting from a parked position. Today it was seriously unsafe.

I was able to "roll" the car over to the side of the road. I popped the hood and felt around the battery. The negative (-) cable was almost too hot to touch. That seems to indicate that there is a short somewhere (from my limited knowledge of electronics. . .). I let it "rest" a bit and then was able to start it again and get home.

I'm going to bring it into the shop-I-don't-really-trust tomorrow because it is close by. Hopefully they will sort it out. When I find out what is wrong I will post it and accept a correct answer or post my own answer.

Thanks for the replies. In my years of driving, I've never encountered this particular issue before.


Update So I just got the car back from the garage-I-have-no-confidence-in (took it there because I can walk to it) and they "couldn't find" anything wrong because the car "wasn't exhibiting the symptom". They said they "reset" some "codes for low voltage" and something about "throttle adjustment when changing the battery". The battery checked out ok. Cost me $130. I guess I should have taken it to the VW dealer straightaway.

I can't really pick a "right answer" since I still don't know what the problem is but thanks for the replies.

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    Welcome to Motor Vehicle Maintenance & Repair! Looks on topic to me :o) – Pᴀᴜʟsᴛᴇʀ2 Mar 4 '18 at 23:58
  • When you get the "click" from the starter, do the other lights stay bright or go out? If they go out you may have a broken cable or a battery with an intermittent broken link inside. If they stay bright, then the starter may be at fault. – Solar Mike Mar 5 '18 at 5:15
  • @SolarMike – thanks for the reply. I wondered if it was just the starter – except that the clock resets to 12:00. The lights seem to go dim – for example, the outside lights (head/tail) which flash when I use the electronic key still flash but dimly. The weird thing is that so far the problem has "gone away" after a few minutes each time it has occurred: power comes back, I can drive, etc. and it seems to happen about once a week. – No Grabbing Mar 5 '18 at 9:35
  • @NoGrabbing have you had any luck with this? I've been experiencing pretty much the same problem with my 2006 Volvo. I don't have a solution and I might just get rid of the car, but I've done a lot of research, so here are potential causes: faulty alternator, dirty battery terminals, faulty battery or a good battery that doesn't match the car spec, faulty steering pump or dirty steering pump fluid, software bug that requires a software update, faulty system (e.g. audio system) drawing too much current, a corroded cable somewhere in the car (yeah, impossible to find), – jfrej Mar 25 '18 at 23:12
  • I had a mechanic install an extra grounding cable for the engine and it didn't make a difference. My local Volvo dealer said they had no idea what it might be and wanted to charge me about $150 per hour for diagnostics which might take a whole day. I would suggest to look for a car electrician in your area. They might have more experience with this kind of issue than a car mechanic. – jfrej Mar 25 '18 at 23:23
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First I would start with disconnecting battery. To verify the connections, then starter unit. Connections may look good to the eye, but the connections are known to cause multiple starting problems. When the both connections are nice and clean, check the connections on the ignition unit, they can get lose also. When your ground and hot are ok, then I would go to check the starter unit. Starters also are known for creating different problems. If all connections are verified, starter is verified, check if there is a starter solenoid unit, make sure this one is working well. Only if all that is done, I would try to shake some main electrical cables, to see if that makes any difference in starting. Sometimes ground is not very solid and it can affect starting or even running of the motor.

  • Also check all the ground cables on the car, both the battery ground and engine grounds. Any one of them having a poor connection could cause this type of issue. Check to make sure the main positive battery cable is tight and not grounding out somewhere, as well as the main positive cable on the alternator. – cscracker Mar 5 '18 at 20:13
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The dashboard clock gets reset to "12:00"

To me this indicates one of two possibilities:

  • the voltage supplied by the battery to auxiliary systems was interrupted (possible cause: an intermittent break)
  • electrical energy demand exceeds electrical energy supply from the battery, so it's like the car is being cranked with a flat battery (excessive current draw, and/or weak battery)

Focusing on excessive current draw

Based on the information provided in the question, the most interesting possibility is that of excessive current draw.

The auxiliaries that consume electricity prior to cranking (key-on-engine-off position) include:

  • cabin lighting
  • fuel pump (for priming the fuel lines)
  • radio/entertainment system
  • security system

Narrowing down the search

If, for instance, there is reason to suspect the fuel pump, a way to confirm this is to:

  • try to crank the engine while the fuel pump is still running (an audible humming sound coming from the back)
  • try to crank it when the fuel pump is not running

If a distinct behavior is observable between the two modes then there is reason to suspect that the fuel pump circuit is contributing to the problem.

  • e.g. always starts when the fuel pump is not running, reproduces issue when the fuel pump is still priming

Similar tests could be performed for the other auxiliary systems that consume electricity.


Other comments

It could be that the battery is weak enough to cause issues under higher loads, but still strong enough to crank the engine over in the absence of extra loads.

Hope this helps to narrow down the problem.

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