parking bulb failure

[d2k]

hi all........ need help urgently!!


just had my mechanic out today fixing my boot lid catch, & my ''check brake bulb'' warning..... boot is fixed but he CANNOT locate this stupid bulb warning.

all bulbs are functioning as they should..???, what can this be if not a bulb issue, im due for MOT next week & i want this silly little problem GONE!!, he says it wont fail but knowing my luck it will.:mad:

is there something else i should be looking at here....


good news is the car is ALL CLEAR on the OBD DTC check, i was expecting a few codes to pop up but she's completely clear


please help me get rid of this niggling problem...

[M-R-P]

That pops up on mine sometimes, I just thump the rear light clusters a few times and it goes away. Ford electrica! D'oh!

[d2k]

lol.... i tried the ''if in doubt give it a clout'' method, no change.


its gotta be one of the rear running lights b/c when the engine is running with NO lights on there's no warnings.

but

switch on running lights & i get ''parking bulb failure'' on the DIM

turn off running lights & warning vanishes

but, if i depress the brake pedal at any time with lights on or off & i get ''check brake light'' pop up on the DIM..????????????



is this warning an MOT fail.....

[Al115]

Could it be one of the LEDs in the high-level brake light? Rare but not impossible.

[d2k]

Could it be one of the LEDs in the high-level brake light? Rare but not impossible.


the mechanic thought that but we checked & they all light up (as far as we can tell), dont suppose theirs anyway i can disable this warning function.. fuse maybe..??

[Al115]

dont suppose theirs anyway i can disable this warning function.. fuse maybe..??

Obviously not or it wouldn't be a Volvo!

Strange that it's logged no DTCs. Are you using a proper fault code reader for the newer cars - one that can read all the Volvo-specific DTCs, not a generic OBDII one?

[d2k]

Obviously not or it wouldn't be a Volvo!

Strange that it's logged no DTCs. Are you using a proper fault code reader for the newer cars - one that can read all the Volvo-specific DTCs, not a generic OBDII one?

not sure what unit it was, it was massive ..held with two hands like a laptop without the lid... not like these code readers i see on ebay, he did say to me it was pretty likely it wouldn't read it

but

i had a little look at it when he was working on the car....it was 100% working after a few seconds a list popped up... all temps, oil / coolant / RPM /airflow all in realtime.... he said ''success'' so i knew it was working & had full access to all ECU's

he came over scrolled to ''CHECK DTC LIST'', the progress bar came up (held my breath) to my amazement it finished & confirmed no active codes.

im heading to volvo after the MOT for a software update (£60) i'll find out for sure then.

[d2k]

right........ i went to the local motor store today & bought a new replacement bulb for everything in the rear clusters, loads of em.

the new ones were actually far brighter than the ones in there which game me hope...

turn on the lights.....''parking bulb failure'' !!WTF!!, every bulb has been changed.. only thing left is the high lvl bulb, or worst case hardware failure.

does anyone know if this bulb warning is an MOT fail even if all bulbs function..??

[M-R-P]

It shouldn't be an mot fail as all the lights are working. Might be forth taking some boot lining out and having a look for a loose connection or frayed wire somewhere.

[Al115]

Check the wire in the hinge. I put a thread up about it a month ago or so.

[TheT6Kid]

When you changed the bulbs did you take a look in the bulb holders and check for any corrosion (white furry terminals) if it wasn't making full contact this may casue you issues? I also think the number plate illumination bulbs are part of this circuit?

[TheT6Kid]

If the bulb works it shouldn't fail the MOT.

[d2k]

thanks all........


i changed the plate bulbs too.. they work well, checked the wiring for the boot b/c my mechanic fitted me a new boot catch the other day so the trim was stripped right back.

the metal contacts were actually white where they touch... i'll give them a clean with some wire wool.

seeing that warning triangle on my dash is starting to grate on me!!

see what they say on Monday.

[Bigrobv70]

the metal contacts were actually white where they touch... i'll give them a clean with some wire wool.


that corrosion will give the bulb contacts a high resistance
thats normally what a bulb warning system uses to check the lights
fair chance thats your problem

Rob