Mk4 Astra Engine management light

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Tue 2 Jan 2007 17:16
Mk4 Astra Engine management light - ivan whitmore
I have just had a Vauxhall dealer check my car with a Tech2, as the engine management light had disappeared.

They told me that the actual light on the intrument panel board had fused and that it was not replaceable, being part of the board. They suggested replacing the instrument panel which costs £200 plus fitting etc. Has anyone tried desoldering this light and replacing it either with a direct replacement or a LED?
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Tue 2 Jan 2007 18:42
Mk4 Astra Engine management light - Dynamic Dave
They told me that the actual light on the intrument panel
board had fused and that it was not replaceable, being part
of the board.


Well you learn something new every day. I would have thought it was a standard bulb, as per all the rest.

::thinking out loud, why didn't Vauxhall fit an LED to illuminate the odometer display, rather than a bulb that can fail regularly::

Back to the subject, why not take the speedo housing out and take a look for yourself to see if the bulb is replaceable.

Details of how to remove
Two Phillips or Torx screws hold the speedo cowling in place - remove. With a bit of fiddling this then can be removed by jiggling between the gap of the dashboard and steering wheel. It is tight, but will come out.
More screws/torx hold speedo housing to dashboard, IIRC.
Finally lift a lever to release speedo housing. No speedo cable to worry about as it is electronic and all the power comes from an electrical multisocket which disconnects when you lift the lever. Again jiggle housing between dash and steering wheel. All the replaceable bulbs simply twist out of the back of the housing.

Refit speedo in the reverse way you removed it.

Word of warning - DON'T turn on the ignition while the speedo housing is out the dash, otherwise you'll have to pay someone to reset the airbag light.
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Sun 7 Jan 2007 11:41
Mk4 Astra Engine management light - ivan whitmore
Thanks Dave

I am going to do as you say and have a look. Whilst I have the chance, I want to put a meter across the fused light filament to see what voltage is there - I can then choose the appropriate LED. I am a bit worried about your airbag light warning - will this still happen if the circuit board is plugged in or are you warning me that it would happen if I switch on the ignition whilst the multisocket is disconnected?

On another point, if I got a used but OK instrument panel to replace mine, is the mileage stored in the instrument panel or elsewhwere? In other words, if I fit a replacement instrument panel will it read the correct mileage for my car or the mileage of the donor car?

I appreciate your help

Regards
Ivan
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Sun 7 Jan 2007 12:39
Mk4 Astra Engine management light - Dynamic Dave
Hi Ivan,

From reports elsewhere, if you turn on the igniton whilst the speedo unit is disconnected from the multisocket the airbag system will log a fault as the checklight bulb is part of the circuit, and the fault would have to be cleared with a fault code reader, such as Tech2.

First thing to do is to remove the speedo unit and check whether it is actually a LED, or a standard capless wedge type bulb.

No idea where the mileage is stored. Sorry.
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Sun 7 Jan 2007 15:39
Mk4 Astra Engine management light - elekie&a/c doctor
The only user replaceable bulbs are for the pod illumination ,odometer ,front fog lights and main beam.All the others are Leds. Access to the leds is very tricky as it requires removal of the instument needles to enable the plastic body of the pod to separate from the printed circuit. on which the leds are mounted.Btw the mileage info is only stored in the pod.hth
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Sun 7 Jan 2007 17:28
Mk4 Astra Engine management light - Dynamic Dave
All the others are Leds.


As I said earlier "Well you learn something new every day."

Thanks for the confirmation elekie.
Btw the mileage info is only stored in the pod.


A case of looking through the back of one of the car mags and ringing someone who offers to *correct* mileages with their laptop on the replacement pod then.
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Sun 7 Jan 2007 20:26
Mk4 Astra Engine management light - ivan whitmore
Thanks Elekie and Dave for further comments. After taking the thing apart, I can confirm Elekie's comments.

I will have to replace the pod now anyway, as when I refitted it, nothing worked except the flasher "repeater arrows"

Ah well, it's been a steep learning curve!!
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Sun 6 Jan 2013 04:59
Mk4 Astra Engine management light - Ramde

I have had same problem, the garage guy detected fault with co2 sensor, he advised to replace coil pack and plugs which I did, when engine when up to 60 m/h then light came back, I took it back to garage, this time he said there could be a fault with sensor I said ok replace it, he replaced brand new bosch brand sensor, after that I took the car to and next day when was driving when engine reaches 60m/h light came back on again, its so frustrating that garage guys don't anything they keep changing parts, I came back home and check all owners manual there is not much information is given Vauxhall, I took it to Vauxhall master fit they said first to replace coil pack and plugs but they also said they if fault still come back then they have to check further, I showed the lists of parts have been replaced, they said there could be fault with head gasket or head may be leaked from in side but they were not 100% sure about fault all they were doing is just guessing and wanted to do experiment I ask for quote they said I can be up 700 GBP, I said car is worth of 1500, I too the car home and decided to sale it as faulty, I advertised on auto trader then I was thinking there should be someone who knows exactly what's wrong, I didn't find any satisfactory answers so decided to repair it at home next day I ordered Vauxhall car repair manual on amazon its around 12 pound something I also order cd and car fault code diagnostic software and usb connecting cable with laptop, I got code said co2 sensor I took first step to know what the sensor actually does in this car red few thing on repair manual, however when I was reading in manual they said co2 sensor no 1, then its sparked in my mind if this is no 1 sensor then there should be a no 2 sensor somewhere I tried to find no 2 sensor and you guys what ? there is a another same size co2 sensor just under the exhaust tank when I tried to removing it it came in out as two parts broken I went on ebay ordered it genuine bosch was about 12 pound replaced it cleared code and took my car to test on coutry side road drove 60 m/h in 3 gear to burn fuel in high raves tried check co2 sensor to see if it detects any o2 but light didn't come on my repairing was successful total cost 12 repair manul+ 20 software cable+ 12 co2 sensor total 44 gbp plus 11 hours work and few tools whch about 20 pound all to gather 66 gbp I still drive it no problem at all took advertise from auto traders, its same as it was before love it amazing

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Sun 6 Jan 2013 08:57
Mk4 Astra Engine management light - John Boy

Well done for initiative, Ramde! That obviously made you feel good.

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