Car start problem

Hi all, I have some problem to start my car these days, and I really want to pinpoint what the problem. So if you have some ideas, just left me know, thanks a lot !

The car is a Volvo 850 wagon with 90K on it. the car runs smoothly once it is started. But for the past 3 weeks, I had quite a few times to have the car jump to start. Once it is started, everything runs smoothly.

At first, it happened almost ever day, if I left car there for 4 hours, I had to have it jumped. So I thought the battery was dead, and had it replaced. But somehow, it does not solve the problem completely. For every 3-4 day driving, I had to have it jumped once.

So I did some test on the battery. If I turn on the engine, and have it running for 1-2 minutes, the voltage number that I reads from the this battery is 13.6. If I turned on all the head-lights, A/C, and radio, with the running engine, the voltage reads as 13.4. Right after the engine was turn off, the voltage was 12.3, and the morning that I had problem to start the car, the voltage reads as: 4.

I notice on my dashboard there is bulb no longer works, the one for the "clock" area. Other than that, all other bulbs works fine.

Another thing I want to ask is how to check the output from the alternator. For this volvo, the alternator is under some other parts. All I can see is a thin wire, and a group of wires joint together.

Thanks a lot for any tips !

Reply to
chunji08
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or alarm system that is flatting the battery. take the positive lead off the battery and measure the current that is being taken from the battery with every thing turned off . I exspect it too be 100mA . IF IT IS MORE ,find where it is going and fix the the problem. if you dont under stand ,put in another alert.

Reply to
m.home4

Hi, I do not quite understand what you have said, could you give me more details ?

Thanks

-CJI

Reply to
chunji08

Use the multimeter that you used to measure the voltage and this time measure the current. In other words set it to current and connect it between the battery + terminal and the cable that he just told you to remove.

Reply to
Malc

Glove box light is a favourite

on my V70 it was an old tracker unit wired to the ignition permanent live that caused the same problem as you described

Tony

Reply to
TMC

Odds are you'll blow the multimeter fuse.

Reply to
Duncanwood

Ok perhaps I should have said "the 10 amp range", what do you expect at

6:30 ack emma?
Reply to
Malc

Even that'll often get you, the mv range between negative post (with lead connected!) & chassis will find large drains as you pull fuses, most cheap meters won't warn you if the current fuse blows so you can get very confused very easily.

Reply to
Duncanwood

All the meters I've seen have the 10 amp range as a big lump of wire - no fuse to blow.

cheers, clive

Reply to
Clive George

Those are even less fun when it goes pear shaped.

Reply to
Duncanwood

All "quality" multimeters (Fluke, et al) have a fused 10A range. It doesn't always save them though....

Cheaper DIY ones will just smoke!

My technique is to use a big lamp (eg headlamp bulb) in series with the circuit being tested first. If sufficient current flows to make the lamp glow other than slightly, *don't* risk the multimeter.

HTH

Chris

Reply to
Chris Whelan

multimeters can be your best friend, or your worst enemy if you dont know much about eletrics

disconnect the negitive lead from the battery. turn OFF the ign (i take the keys out and put in my pocket- apprentices nearby) now connect the multimeter on the 10 amp setting and connect between the negative battery post and the negative main earth lead (the fuse wont blow cos ign is off). now pull each fuse out in turn and watch the display to see which fuse makes the figure drop you wont get 0.00 but anything over 0.20(approx)is not good

Reply to
ford_technical_

Chris Whelan wrote in news:ggpBf.108857$ snipped-for-privacy@newsfe4-win.ntli.net:

Mine's only a cheap Robin (about £15 IIRC) and it has a 10A fuse. My old Maplins one has an unfused 20A range.

Good idea. Certainly took the 10A fuse out quickly when an alternator diode went down on my dad's car. How the battery (already 8 years old at the time) survived such complete drainage I'll never know!

Reply to
Stu

I had a similar problem - turned out that the Sony car stereo in "off" mode was drawing about 4 amps constant for some bizarre reason. Worked it out like you just desribed - took car back to dealers (6 months old) and told them to fix. Came back with same stereo, same problem - no fault found.

When the car arrived back the next day on an AA van - they took it more seriously.

Nobody could believe the stereo was drawing that much full stop without blowing any fuses!

Cheers Dan.

Reply to
Dan delaMare-Lyon

4A? 48 watts (ish)? Shouldn't blow the fuse on most cars. Mine has a 30A feed IIRC.
Reply to
Tim S Kemp

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