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Discussion Starter · #1 ·
Just sorted reverse selection out (sort of), and this morning the brake light check warning will not go off on my 96 9k 2.0 LPT. checked brake lights(clusters and high level), tail lights, side lights and headlights and all seem OK. Boot courtesy light havs been inoperable since I got the car, so don't think it is that.

What else does this warn of that I need to check?

TIA,

Pete
 

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When you say it will not go off, do you mean that it's on all the time? The pictogram should only light up when a light is turned on but the bulb has failed. I.e. the brake light failure should only light up when your foot is on the pedal, and the rear light failure should only light up when the side lights or headlights are turned on.
 

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Discussion Starter · #3 ·
Usually, pictogram with rear lights is lit at start, and goes off when touching brake for 1st time. However, does not go off when touching brake.

Just starting luch break, so will check contacts and stuff in clusters and see what happens.

Cheers,

Pete
 

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I have a similar situation to efcbluepete. My 96 2.0 LPT CDE Auto also has a u/s boot light and, on starting, the pictogram appears to indicate a rear light failure. In my case, pushing the brake pedal switches the pictogram off.

As far as I can tell all lights are OK so perhaps this is a random glitch in 95/6 cars or is somehow related to the boot light. I had a service at a main dealer and nothing was reported to be out of order (although I hadn't asked them to check this as I wasn't particularly bothered by it).

Next time I'm near a parts shop I'll get a new bulb for the boot light and see if that changes anything.
 

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Pete,

You hadn't posted when I started typing (I'm assessed on a words per hour basis)

From what you're saying the 'lit up' rear may be a 'normal' feature at first start but there's no mention of that in the Handbook which is pretty comprehensive about most things.
 

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the pictogram electronics seems to be pretty sensitive to small variations in the resistance of the lighting circuits
My pictogram tells me that there is a brake light out even when all are working (I have also replaced the high level rear bulbs with an led strip as all the contacts had completely corroded !)
I guess as these cars get older, variations in contact resistance will become more and more significant and will cause these false readings
 

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Originally posted by Gordy:
[qb]I'm pretty sure that there are 2 brake light bulbs in each corner. [/qb][/b]
I think you'll find that there are two tail lights at each side, but only one brake light, intergrated with one of the tail lights. This is so that a single taillight bulb failure doesn't leave you with a dark side (with or without a moon!).

Perhaps the 96 cars are different than the 93/94 cars, as my pictogram goes out after starting and only displays a fault when the brake pedal is pressed (if there is a bulb out). Having the brakelight failure lit up until you press the brakes and all is well means that it will stay permanently lit if there is a problem.

Smokee,

My failure lights were triggered when I had two out of the four high level lights fail (one was not enough). These bulbs are 2 x 5W and 2 x 3W in the UK, so somewhere around half an amp reduction in current is enough to trigger the system. If you have replaced the high level lights with LEDs (which use only milliamps), it's no wonder the failure lights are on. When certain other manufacturers started using LEDs for brakelights, instead of redesigning the bulb monitoring system, they just put a resistor in parallel with the LED cluster, so that the current draw is "correct". You could do the same.
 

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This is probably a bit left field but my girlfriend had a very early 9-3 and when you started that it showed 'Check Brakes' on the SID until you used pressed the pedal.

You've not got the 9000 equivalent going on here have you?
 

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as smokee says,the resistance is critical and can show a blown bulb even when working.this is due to the fact that as bulbs get older the resistance in the filament increases because they get thinner(thats why they eventually break).this can fool the pictogram thang into thinking theres a bulb gone,PHEW!!.answer..change the bulbs in that curcuit.(even if working!!)
 

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Discussion Starter · #13 ·
Aeroboy, it is the same as you describe with the check light per 9-3 (my boss used to have one, until the "tax on emissions" regulations came on for company cars).

Got help and found, as mentioned in an earlier post, one of the lights in the cluster had gone, but as the other was still working fooled me into thinking all was well as I could see reflected light from both sides and high level.

Will get new one today and some spares.

P.S. Smokee, where did you get the LED strip from? DIY or bought in part? Have just finished testing some high brightness white LEDs and might look into replacing the high level set (prone to probs, from previous threads).

Thanks,

Pete
 

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efcbluepete ...

it was a cheep aftermarket red led strip that someone had fitted to one of my £150 900 specials
I just stripped it down and it was perfect size to fit in where the old bulbholder was
I could do with a second row to finish it off but it looks ok (imho) and reasonably bright

so a 10 ohm 20 w resistor it is....
 

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Indeed I did... I went for 6 LEDs (interestingly there are 6 "bays" in the housing but it is only fitted with 4 lamps) because that avoided the need to have to use any series ballast resistance. I can't remember what resistor I ended up using... I'll check later. I simply driled the outsie 2 bays to take the ¼ hi bright LEDs. I also painted the bays silver.

A quick calc though from Mark B's figures... total of 16W @ 12V gives a current of 1.33A and a resistance of 9 Ohms. The current draw of the LEDs will be of the order of 20mA so is negligible.
 

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Mark,

am I correct in thinking that you used six 2 Volt hi bright white LEDs, or did you use red ones? How does this compare with the original brightness of the bulbs? I am tempted by six ultra bright red leds!
 

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Mark,

There's no point in using white LEDs... the energy for the other colours they produce to make white light will only be filtered out by the red lens


So, hi-brite red are the way to go, 6 in series, I reckon they are about the same as the incandescent lamps- Scaero might be able to comment on how they look in daylight , here's how they look in dusk (camera shake and all..)


Turns out I used two 12W 47 Ohm resistors to cure the pictogram problem.
 

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Originally posted by Mark E:
[qb]Mark,

There's no point in using white LEDs... the energy for the other colours they produce to make white light will only be filtered out by the red lens   [/qb][/b]
Glad to see that you are almost as pedantic as me then!

Two 47 Ohm resistors in parallel: doesn't that equate to effectively a 23.5 Ohm resistance, therefore some way away from the calculated 9 Ohms?

I am puzzled.
 
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