Adjust voltmeter

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jamescarruthers
480 Is my middle name
Posts: 1666
Joined: Mon Jul 07, 2003 3:19 pm
Location: Cambridge

Adjust voltmeter

Post by jamescarruthers » Fri Feb 05, 2016 12:57 pm

I saw a post on here within the last year about adjusting the voltmeter in the car. Mine has been reading 8-9V for a while and is obviously lying. I thought I'd try a tweak before replacing.

Can anyone else remember it? I have browsed and searched but with no luck.
1987 Volvo 480 ES, 507274, 217 - Red (Ness)
2001 Volvo C70 2.4T convertible (Olivolvo)
2008 Mini Cooper convertible (Mau)

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES auto
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo auto
E981 KHM -- ES (509849)

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brinkie
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Posts: 606
Joined: Mon Apr 21, 2014 11:20 am
Location: The Netherlands
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Re: Adjust voltmeter

Post by brinkie » Sat Feb 06, 2016 9:15 pm

You can adjust the voltmeter with the potentiometer on top of the meter and by moving the needle itself. You need to open up the unit in order to reach it.
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But the accuracy is horrible at best, it's nothing more than a vague indication of battery voltage. I've tried to calibrate the meter and this was the best result I got:
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Robert.

Present cars: 1994 Volvo 480 GT 2.0i Vase Green, 2010 Volvo V70 2.0F Momentum Mystic Silver
Past: 1981 Talbot-Matra Murena 2.2 Rouge Mephisto, 1995 Volvo 480 GT 2.0i Paris Blue

User avatar
jamescarruthers
480 Is my middle name
Posts: 1666
Joined: Mon Jul 07, 2003 3:19 pm
Location: Cambridge

Re: Adjust voltmeter

Post by jamescarruthers » Sat Feb 06, 2016 9:30 pm

Excellent, thank you. I will have a go soon at this. Hope it's not broken as I can understand why it would just drop down so low!
1987 Volvo 480 ES, 507274, 217 - Red (Ness)
2001 Volvo C70 2.4T convertible (Olivolvo)
2008 Mini Cooper convertible (Mau)

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES auto
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo auto
E981 KHM -- ES (509849)

User avatar
brinkie
480 Expert
Posts: 606
Joined: Mon Apr 21, 2014 11:20 am
Location: The Netherlands
Contact:

Re: Adjust voltmeter

Post by brinkie » Sat Feb 06, 2016 10:14 pm

I would try and measure the battery voltage first with a digital multimeter, just in case the voltage gauge was right after all... :twisted:

If you want to calibrate the lower end of the range without a variable power supply, use a 9V battery.
Robert.

Present cars: 1994 Volvo 480 GT 2.0i Vase Green, 2010 Volvo V70 2.0F Momentum Mystic Silver
Past: 1981 Talbot-Matra Murena 2.2 Rouge Mephisto, 1995 Volvo 480 GT 2.0i Paris Blue

User avatar
jamescarruthers
480 Is my middle name
Posts: 1666
Joined: Mon Jul 07, 2003 3:19 pm
Location: Cambridge

Re: Adjust voltmeter

Post by jamescarruthers » Sat Feb 06, 2016 10:38 pm

What is "19", between the key and pin 5. A resistor?
1987 Volvo 480 ES, 507274, 217 - Red (Ness)
2001 Volvo C70 2.4T convertible (Olivolvo)
2008 Mini Cooper convertible (Mau)

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES auto
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo auto
E981 KHM -- ES (509849)

User avatar
brinkie
480 Expert
Posts: 606
Joined: Mon Apr 21, 2014 11:20 am
Location: The Netherlands
Contact:

Re: Adjust voltmeter

Post by brinkie » Sat Feb 06, 2016 11:07 pm

A fuse. The actual fuse depends on model year, there are three different fusebox layouts if I recall correctly.
Robert.

Present cars: 1994 Volvo 480 GT 2.0i Vase Green, 2010 Volvo V70 2.0F Momentum Mystic Silver
Past: 1981 Talbot-Matra Murena 2.2 Rouge Mephisto, 1995 Volvo 480 GT 2.0i Paris Blue

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