Instrument cluster bulb replacement

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Jugostran
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Instrument cluster bulb replacement

Post by Jugostran »

Hello everyone,
This will be a short one. Several bulbs in my instrument cluster went out. I wanted to fix them, so I bought a 30 pack of T5 12V bulbs. The problems started once I went to test the new bulbs in the door open display (which uses the exact same T5 bulbs to my knowledge). After testing it, it seems like none of my new bulbs are working. Is this because the door open display uses a different voltage, or are there different types of T5 bulb? Either way, I tested the new bulbs with my multimeter and they seem fine to me.
Any help would be greatly appreciated!
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Re: Instrument cluster bulb replacement

Post by rutter123 »

I found it best to replace the bulb holders as well and clean all the contact tracks and the pins in the 5 plugs this solved the problem for me
Then bench test it before fitting.
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Re: Instrument cluster bulb replacement

Post by white exec »

The Haynes BX manual has the circuit diagrams for the instrument panels and the doors open display, and identifies the pin numbers on their connectors.
All the bulbs are T5 (W1.2W) 12v 1.2w capless.
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Re: Instrument cluster bulb replacement

Post by Jaba »

The contact tails on each bulb need to be in the correct position to make contact in the holder. Perhaps your new bulbs are not quite right and need some bending.
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Jugostran
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Re: Instrument cluster bulb replacement

Post by Jugostran »

Thank you all for your help.
I will try cleaning the sockets and adjusting the contacts on the bulbs. Also, judging by the spec, I think I have the correct ones. I will update you if any of these fixes work!
EDIT:
The ones I got are T5 (W1.2W) 12V 1.2W
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Jugostran
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Re: Instrument cluster bulb replacement

Post by Jugostran »

UPDATE:
It works now! I just fiddled with the contacts and tried a few bulb/socket combinations and now all is working. I also figured the best way to test the bulbs pre-install is with a multimeter in continuity mode. Basically, anything around 0.13/0.14 ohms indicates the bulb and socket are good. I hope this thread can help people who plan on doing Citroen BX interior bulb replacements in the future!
Also, I sincerely thank all of you who offered tips. Your advice is greatly appreciated!
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Re: Instrument cluster bulb replacement

Post by white exec »

Good result! Apologies for the slip with the bulb spec....W1.2W is correct. Have corrected my post.
Glad it's now working.
To maximise instrument panel bulb life, try not to operate them on maximium brightness all the time. Just a little bit of dimming makes a big difference.
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Jugostran
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Re: Instrument cluster bulb replacement

Post by Jugostran »

white exec wrote: Sat Jan 15, 2022 5:28 pm Good result! Apologies for the slip with the bulb spec....W1.2W is correct. Have corrected my post.
Glad it's now working.
To maximise instrument panel bulb life, try not to operate them on maximium brightness all the time. Just a little bit of dimming makes a big difference.
Thanks for the tip.
The cluster looks excellent now!Image
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