Volvo 740

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Mon 23 Jun 2003 10:33
Volvo 740 - Peter
An electrical fault on my 740 is annoying me. These cars have a bulb failure warning light which is quite useful in normal circumstances. However, when I apply the brakes the light comes on but does not extinguish when the brakes are released. After around 5 minutes of no braking the light goes out. All the brake bulbs are new, contacts seem clean.

Comments much appreciated. Thanks.
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Thu 26 Jun 2003 21:37
Volvo 740 - pettaw
I think there's a relay for the warning light that detects differences in resistance. Maybe its sticking or something.
The experts are to be found at the Volvo Owners Club. Theres a forum at www.volvoclub.org.uk

You have to register to post but registration is free, but to receive magazines/other member perks, you have to join the club.
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Fri 27 Jun 2003 11:15
Volvo 740 - Cliff Pope
This is a well known feature with Volvos. Usually caused by poor quality or non-matching bulbs, or a sign that a bulb is about to give out. Try different bulbs.
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Fri 27 Jun 2003 12:20
Volvo 740 - Aprilia
I had this problem on a BMW with similar system. Had to buy bulbs from the dealer that were closely resistance matched. Also any poor connections in the circuit (even if the bulb works OK) will lead to a malfunction indication.
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Sat 28 Jun 2003 07:48
Volvo 740 - Cliff Pope
For future reference the answer to any Volvo question can usually be found at Brickboard.com. It is mostly American-based, but I have found posting a question there usually brings lots of experienced responses. Because of the time difference I often post a question in the day and get a reply by evening.
They have about 100 times as many subscribers as our own Volvo club, useful as that is.

Good luck
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Mon 30 Jun 2003 10:20
Volvo 740 - Peter
Thank you all for your suggestions.

I eventually traced the fault to an ill fitting front N/S day running light bulb holder. The locating lugs had sheared allowing the bulb to rattle around too much. A S/H holder was aquired and fitted. I did buy a set of bulbs of the same type and fit them to be on the safe side. All's well now.

Thanks again.

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