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Intrument light + Bulb light problem Topic is solved

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Metallo
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Intrument light + Bulb light problem

Post by Metallo »

Hi guys,

I have a940 of 1997, Yazaki dashboard and I have an issue with one of the main 4 bulbs that light up the instrument (3W).

A picture will better clarify what I am talking about.

Image

The bulb will light up after about 45 min.

I took the multi-meter and verified both bulb + bulb holder, they are both OK.
As a second test, I removed one of the working bulb+holder assembly and tried if it would work when snapped in the not working bulb spot, no-go.

This leads me to conclude that the issue is not bulb-holder related, but something in the circuit of that assembly.
Obviously, when the thing heats up, after about 45 min., it works.

Can you help me from here?

Thank you!
Alex
Polar 940 Turbo SW - 1997
XC 70 AWD 2.5 - 2006

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RickHaleParker
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Post by RickHaleParker »

Trace the paths. Look for loose screws, cracked printed circuits and defective solder joints. Any of which can open and close with thermal expansion.
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Metallo
Posts: 258
Joined: 18 January 2004
Year and Model: XC 70 AWD 2.5 - 2006
Location: Canada - NB
Has thanked: 7 times
Been thanked: 6 times

Post by Metallo »

RickHaleParker wrote: 27 Oct 2019, 14:08 Trace the paths. Look for loose screws, cracked printed circuits and defective solder joints. Any of which can open and close with thermal expansion.
Hi there,

It was a defective solder under the rheostat, I have redone all the soldering and everything works as new.

Thank you,
Alex
Polar 940 Turbo SW - 1997
XC 70 AWD 2.5 - 2006

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