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Discussion Starter #1
Hi,

Happy New Year !

My 147 Keeps blowing the front Right Side Light Bulbs.. :mad:

I have been through 4 or 5 bulbs now..

All Bosch ones from differnt shops, After the first couple I was careful not to touch the bulb with my hands, thinking I was getting grease on the bulb.

A new bulb will last for a week or two of driving... say about 500 miles or so with lights on and off.., so it's not an instant thing..

Any one had this problem ?

It's a H6W bulb.. FYI

SB
 

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I had similar problem with my 156. I examined all the earth fixings, cleaned, refitted and covered with waxoyl. Eventually replaced bulbs with led's and no more hassle.
 

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Yeah just replace with can bus error free LED bulbs.

Some people say it could be a failing regulator.

Does your light cluster get moisture in it?
 

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+1 for canbus leds......i went that way...£2 inc postage for a pair from hong kong....a week or so wait but worth it
 

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Discussion Starter #6
Thanks for that.. no the Cluster seems dry as anything.. I've ordered some LED's so I'll see if they do the trick.. (or just burn out the test circuit !)

SB
 

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I have the same problem, which is driving me mad, any chance of a tip for a complete car mechanics dunce.

(I can change bulbs etc but not much more than that).

If I want to try and stop my 147 repeatedly blowing bulbs, the suggestion seems to be swap them for LEDs, but can anyone tell me step by step how I do this.

Whats a can bus?

Is it as simple as buying some and replacing the existing bulbs with them?

Thanks
 

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Discussion Starter #8
I changed mine for LED's and not had a problem since.

It's as simple as typing H6W led into eBay.

The CAN bus, (the 147 doesn't strictly have a CAN bus) is protocol and electrical specification for transmitting data around the car. Diagnostic info on sensors, sensor info, bulb info etc.. All connected to a common bus, so the cars computer(s) can read, diagnose, and act on the info.

The 147 had a diagnostic circuit in place to tell the driver if the bulb (in this case) has blown. It does it by passing a low voltage across the bulb, using one of the two +ve lugs on the bulb. Not enough voltage or current to light the bulb, but enough to tell if there is a circuit.

The LED with can bus, you see on eBay, simply have a resistor in place to fool the car into believing the bulb is ok, as you can't pass low voltage/current across a diode.

So yeah go for it, you will graze your knuckles getting them out, but the owners manual will help you enough.

SB
 

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I've been plagued with blowing tail and numberplate lamps on a motorcycle in the past. Only the more delicate 5w filaments were affected, 21w stop and indicator filaments survived. They only blew when the engine was started with lights on. If they were off, the bulbs were fine once it was running. I put up with this for years, and got through maybe 20 bulbs when, sooner or later, I'd again forget to turn lights off before starting.

I went right through the rear loom checking and cleaning everything several times.

Eventually I found a corroded connector between alternator output and battery, which appears to have put a spike into the loom as the resistance caused by the corrosion was overcome. It became easy to find because it deteriorated to complete open circuit and the alternator burned out its rotor. I tested the regulator, it was still fine. No more blown bulbs after fixing that connector and fitting a s/h alternator.
 

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@ShiftyBloke

Thanks for that explanation. Helps me out a lot. I'll get on ebay and order some.

Tried to change the bulb last night for a normal one, spent half an hour fighting the thing in the dark to manage to get the fiddly bugger out, then discovered by bulb kit didn't have the right bulb in it anyway.

I reckon we've done six various assorted bulbs in a few months on the car. Driving me mad.
 
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