General: 70: Parking Bulb Failure

Hi All

I own a V70 D5 2002. This weekend the diagnostic display told me that i had a parking bulb failure.

I checked all the bulbs and yes the front nearside parking bulb had gone. I fitted a replacement and it worked OK.

The only problem is the diagnostic display is still saying parking bulb failure.

I have checked the following lamps, front and rear parking lamps, all lit OK, number plate lights all ok.

Have i missed any more lamps in teh parking light catagory.

I have also tried removing fuse 32 from the passenger compartment which is the central control module. Still the same.

Therefore if all lamps are working is it worth disconnecting the battery for a minute to reset everything. Will this cause any problems with the main ECM if i do this and is there any guidlines i should follow when disconnecting/reconnecting the battery.

Any advise would be greatly appreciated.

Regards

Mark

[Chris_Rogers]

Not sure about the latest model but the older ones were quite picky about the type (make) of lamp fitted and particularly being the same each side of the car. You could try swapping lamps left to right but yoiu may have to replace both lamps with the same make.

[ShadeTek]

Can I hi-jack this post about a question with bulb failure units? I have read that the failure unit senses the current through each lamp and will then notice the differecnce in the current and light the MIL. If you were to replace all the lamps in the circuit with LED ones, would it then function without lighting the MIL?

[Alec Dawe]

Originally Posted by markv70D5

Hi All

I own a V70 D5 2002. This weekend the diagnostic display told me that i had a parking bulb failure.

I checked all the bulbs and yes the front nearside parking bulb had gone. I fitted a replacement and it worked OK.



Therefore if all lamps are working is it worth disconnecting the battery for a minute to reset everything. Will this cause any problems with the main ECM if i do this and is there any guidlines i should follow when disconnecting/reconnecting the battery.

Any advise would be greatly appreciated.

Regards

Mark

Don't think that disconecting the battery will make any difference. As has been said, the bulb failure works just by comparing the current taken by each side of each curcuit it works on, and is very, very picky about bulbs. My 240 hates different brand headlamp bulbs, and can be fussy about rear light bulbs too.
I would suggest that you always buy bulbs in pairs, and change them in pairs. Most often, this will solve the bulb failure still on problem.

Alec

concerning bulb failure lights on the dash...that if the bulb is not setting completely correctly on the connection or is "about to go" (maybe the other parking light) the light will be on.

I had questioned it when I was getting the msg periodically but none of my bulbs were out...then one finally went.

[cootuk]

regarding LEDs I thought you had to add an extra ballast resistor to fool the computer in to thinking you still had the power draw of normal bulbs?

http://reviews.ebay.com/LED-Conversi...:-1:LISTINGS:2

Thanks for the replies, i must admit the manual says the parking bulbs are 5w 12v. I obtained them from Halfords so i will try and get them from a dealer.

There must be a specific resistance the diagnostic system is looking for through the lamp.

A previous post comments that it is the current that the system is looking at, if the bulb is not switched on no current will flow, therefore it must be resistance its monitoring as the bulb failure warning comes on even if the bulb is not switched on.

I will get a bulb from the dealer and measure the resistance compared to the Halfords bulb and see if there is a difference.

Thanks

[ShadeTek]

Originally Posted by cootuk

regarding LEDs I thought you had to add an extra ballast resistor to fool the computer in to thinking you still had the power draw of normal bulbs?

http://reviews.ebay.com/LED-Conversi...:-1:LISTINGS:2

I believe it measures the difference in the current between the individual bulbs. So if all the bulbs/leds drew the same amount, there would be no difference in current......unless a very low current triggered the MIL.