Rear Brake Bulb Failure + Aircon not lowering temperature

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Thread: Rear Brake Bulb Failure + Aircon not lowering temperature

  1. #1

    Rear Brake Bulb Failure + Aircon not lowering temperature

    Its been a while and probably 30,000 miles of trouble free motoring, however -

    SAAB 9-3 1.9Tdi Vector Sport '56 plate

    Getting an intermittent fault on dash telling me the rear left brake bulb has failed. I've replaced it and still get the intermittent fault... any ideas?

    also,

    My aircon was a bit noisy so 6 months ago I went to kwikfit and had it recharged. It seemed to be fine.
    Now, however, it doesnt matter if the aircon is on or off, the air blown into the cabin is not getting chilled. I also noticed no noise from the aircon when it is on, and dont detect the very slight change in engine tone when its switched on. ANy ideas?

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  3. #2

    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    The engine note will change when the climate is switched on as a clutch/solenoid switches/activates so the a/c pump is driven from the ancillary belt putting more load on - dipping the revs.

    Re your aircon now not working . Sounds like you have a leak in the system. Kwik fit should have picked that up when they re-gassed. As a side, run your a/c for at 30-60 mins a month summer or winter to keep things working The rubber seals perish/shrink letting the gas out.

    Re you bulbs, check the connector blocks onto the lighting circuit board surrounding the light bulbs are tight

  4. #3

    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    thanks, will check the connector blocks to the light clusters...
    On aircon, I generally have it default to on so it tends to be used all the time, only being off for brief periods summer or winter.

  5. #4
    Saab Fan
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    Leicester
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    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Don't want to jump in on your thread Gordan,but I have exactly the same 2 problems on my '06 vert. SID tells me that the high level brake light on boot is out (it isn't).Only happens rarely & I think it is maybe something to do with the boot not being shut really tight,even though it appears to be. As for aircon,I too had it topped up at Kwikfit,never really seemed to chill properly after.Should I be able to hear the compressor clutch when it engages? I suspect the clutch isn't driving the compressor as I can't hear anything when AC turned on. (fuse & relay ok)

  6. #5
    Saab Junior
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    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    [QUOTE=the zohan;919529]The engine note will change when the climate is switched on as a clutch/solenoid switches/activates so the a/c pump is driven from the ancillary belt putting more load on - dipping the revs.

    If your aircon is out of gas then it will not allow the compressor to engage when you select.This is to prevent it burning out or destroying the compressor.Its a built in safety system.That is why you are not hearing any note change from the engine when you select aircon.Repair leak and regas the system then it will work.

  7. #6
    Saabisti
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    wantage in oxfordshire
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    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Kwick kill will only check at low pressure and for this reason give you 2 weeks in which to take it back if it leaks and get a refund.

    Take it to a company who can check at full pressure to see if you have a leak, and if so do a dye test to find out where.
    Condensors are a common place due to stone damage but there are lots of other places that can fail and leak also.
    As said "no gas" will stop compressor working, so gas is first place to check.
    Saab charged £614 a year ago for new+fitting of condensor, but i was covered under warenty (aftermarket)

    Good luck

  8. #7

    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    thank you for all responses...
    On brake lights, I ended up checking the block connectors to both rear light clusters, replacing both brake light bulbs and also checking the engine compartment fuse box, pressing in every fuse to make sure they were seated properly. The SID warning has not come on today so we will wait and see.

    On aircon, I never realised a leak would stop the system working altogether and given the symptoms I reckon thats maybe what is happening. Will try a specialist aircon place rather than kwikfit.

  9. #8
    Saab Fan
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    Sep 2010
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    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Quick update: just had gas checked (for free by Kwikfit) they said it was ok,but CC still not working.Think compressor is not turning on so either sensor is faulty saying no gas when there is(don't know where sensor is) or compressor faulty (hope not!)As I said earlier fuse & relay seem ok.
    Anyone know any good aircon places around Leicester?

  10. #9

    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    still getting rear brake light failure at random intervals whilst driving...

  11. #10
    Saab Junior
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    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Quote Originally Posted by GordonM View Post
    still getting rear brake light failure at random intervals whilst driving...
    Gordon...have you checked if the bulb is working.If it is then the saab ecu measures resistance across the bulbs.If it detects a rise or fall due to the filament in the bulb starting to deteriorate then it will bring up the warning on the SID saying bulb or lamp fault so as to change before it actually does blow.If its new bulbs then check the security of the lamp holder.Hope this works.

  12. #11
    Saab Fan
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    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Another update:had AC checked by specialist,leaking condenser-so much for Kwikfit's leak test that said it was ok! Unless you know for sure all you want is a re-gas,then use a specialist AC place.
    Oh,& does anyone know where part number for condenser (2006 9-3 2.0t petrol 'vert) can be found? Thanks.
    Last edited by saabmale; 05-30-2012 at 03:43 AM.

  13. #12

    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Rear brake light error is almost certainly down to a loose connection/bad earth.
    Was in the car wash today and parked up (engine running) when the guy opened the boot to clean the rim, closed the boot (solidly) and the error popped up on my SID.
    I reckon the small flexible metal strip the base of the bulb touches is looking a bit 'blackened'. Will try and clean it and refit the bulb to ensure a sound connection.

  14. #13

    Re: Rear Brake Bulb Failure + Aircon not lowering temperature

    Just to post a solution...

    Turns out a 'new' Halfords bulb was faulty. When I eventually tried switching the right and left brake bulbs, the error switched from left to right indicating it was the brand new bulb causing the problem (both were new).

    I have now replaced both bulbs again but with Bosch bulbs and error seems to have disappeared.

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