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  #13  
Old 11-24-2011, 01:49 PM
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Re: Overhead computer display failure

Its right hand drive. The BCM is mounted on the back of the fuse box, with 4 torx screws. I found it easier to take the whole fuse box unit out, then remove the Body Control Module
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  #14  
Old 11-25-2011, 03:14 AM
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Re: Overhead computer display failure

Thanks for that Farmer. Wondered why I couldn't find it.
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Old 11-25-2011, 06:10 AM
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Re: Overhead computer display failure

To be sure that the EVIC itself is not at fault, you can do a selftest on it. With ignition in off, press and hold the C/T and RESET buttons and switch the ignition in on. The EVIC display will show the software version until you release both buttons, then a self test will be done and " Pass self test" shown if all ok, or "Failed self test" when the EVIC has an internal fault. It also checks if the PCI bus is working properly and will show " Not receiving J1850 message" when there is a fault with the data bus.
As far as i know the info for calculating the fuel consumption etc is coming from the PCM and not BCM.
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  #16  
Old 11-25-2011, 11:53 AM
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Re: Overhead computer display failure

Tony, my biggest confusion her is how your getting "26.7 Average consumption" ! Im only sqweezing 22.8mpg out of my 2.7crd, although most of that is urban/semi urban rush hour commuting. Hopeing the mpg is better on a good run to the coast !
I still dont know if that overhead computer is calibrated for US gallons, not UK ?
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Old 11-26-2011, 06:31 AM
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Re: Overhead computer display failure

Hi Frank,

thanks for the EVIC (what does this stand for?) self-test info. I did as you suggested and it passed O.K. Only slight problem is that the other control modules don't like you doing it. The fuel gauge showed empty, which I knew it wasn't, the overhead display said "0 miles to empty". The 'disconnect/reconnect' trick put everything back to normal though. The fuel gauge then registered as properly as fuel gauges do, and the 'miles to empty' gradually climbed up to something sensible.

Hi GCUK,

the figure I quoted for consumption was just a random selection, but I do get that kind of consumption particularly if I fill and reset before a longish trip, when I can see as much as 30mpg. Urban cycle I get low 20s, about the same as you. My wife tends to get even lower figures than I do, but if I said anything the reply would probably be "...O.K. then, you can drive everywhere....".

Cheers

Tony N
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Old 11-26-2011, 07:28 AM
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Re: Overhead computer display failure

Hi Tony,

EVIC stands for Electronic Vehicle Info Center.
The fuel gauge gets its info regarding fuel level from the PCM via the PCI bus. Also the EVIC gets its info via the PCI. The PCI bus itself is ok, otherwise the selftest should have shown it.
When you loose the fuel gauge reading after doing the selftest, then you have a good change that the problem is somewhere in the EVIC.
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Old 11-28-2011, 11:54 AM
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Re: Overhead computer display failure

Another update on mine. Pulling fuse 7 for the BCM, allows all windows, courtesy lights, EVIC functions like mpg to work as normal again. This would lead me to believe the BCM is locking up. But why? Faulty module or faulty wiring? Needs further investigation. Will keep you posted
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Old 11-28-2011, 12:48 PM
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Re: Overhead computer display failure

There are also 2 other power inputs to the BCM, fuse 22 and 28. This are no constant power inputs, but depend on ignition switch position. With fuse 7 out and the ignition in on, do you still have all functions working?
The BCM could be faulty, but also one of the output circuits from the BCM. You could disconnect the C1 and C2 connectors on the BCM one by one or both together and see if there will be any difference.
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  #21  
Old 11-28-2011, 02:20 PM
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Re: Overhead computer display failure

Yes, I seen from the electrical diagrams that there are two more switched supplys, one from the run-acc and and one from the run-start key position. Pulling fuse 7 kills the interior lights etc, so nothing works with the fuse out. I think I will start to look at the output circuits incase one is causing a fault. There is no common link as yet to when the power windows will stop working. Even leaving the ignition on for 5 minutes will cause it to "lock out". other times it will go when driving within a few minutes
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Old 01-13-2012, 12:05 PM
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Re: Overhead computer display failure

Hi Farmer,

as I indicated in my "Overhead ........... revisited." post, it seems my previous efforts have not been successful. It being nice and dry today (Fri 13th Jan), perhaps I should have left well alone bearing in mind the date, I thought I'd have a go at getting the BCM out.

I remembered that a certain 'Farmer' said "....I found it easier to take the whole fuse box unit out...". Well done you! It took me 2 hours to find that to remove the lower trim it is necessary first to remove the trim above the steering wheel. Then, after removing the fuse cover and the lower trim, I found the 2 10mm headed bolts that hold said assembly to the metalwork; disconnected all the cables I could find, but couldn't find what the hell was holding the assembly at the top. It's obviously not bolted up there because the unit moves back and forth but won't come down.

By this time the light is failing so, after ascertaining what size Torx tool is needed to remove the BCM from the fuse unit, I re-mounted the fuse unit, reconnected everything and left the trim off.

Of course, all the above was done with the battery disconnected so when it was reconnected everything seemed O.K.

Next dry day after it goes down again, if it does, I shall remove the BCM from the fuse unit (unless that is, that you can tell me the trick to getting out the whole assembly in one piece, (pretty please) and have a look at it. If it doesn't go down again I will assume that it was a dodgy connection causing the problem. One lives in hope.

Wish me luck.

Tony N
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Old 06-22-2012, 06:05 PM
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Re: Overhead computer display failure

This nut has taken weeks to crack and the final piece of the puzzle was your right here on this site.

My issue was that a few weeks ago my windows were acting erratic and finally they stopped working. The right rear was stuck all the way down and the left front was half way. The sunroof worked, but that's about it.

Every single google search fix suggested replacing BCMs, PCMs, door switch panel, PCI's, etc. I even saw a great YouTube vid on how to replace the BCM behind the fuse box. (Thank God I didn't do it!) After some digging, it turned out to be a severed ground wire (black) inside the boot between the body and the door. (Or the large orange wire with pink tracer too.) Apparently this is quite common. REPAIRED. Now the electric door lock works and so does the mirror control, but still no power to the windows or door light. Every plug was reseated.

Add the EVIC which is going nuts too now. It isn't registering temp, econ, mileage, etc. The interior lights are now also malfunctioning, stay on and have to be turned off manually. The headlights only work manually, not in auto. All other exterior lights work fine. I do the EVIC test (C/T & Reset with ignition turned on) and get a J1850. Most sites say it's a done deal, dealer fix and/or you have to replace something expensive - NOT necessarily!

I look at the door fuses in the engine compartment, check continuity and even rearrange them. This didn't work either. So I check fuses 27 & 28. 27 was blown and replaced (just coincidental I think). No change. Windows still don't work.

Thanks to this thread, but not completely the cure, the final piece to the puzzle was to pull fuse #7, #22 AND #28 together! I left them out for a while and replaced them.

After weeks of frustration, the problem was finally fixed. I'm only a DYI mechanic, but fly an airplane that's a robot (over 300 computers). Sometimes a computer needs a gentle reset/kick (several breakers in a special order or in unison) which is my guess here or a complete power down (airplane reboot/ car battery disconnect). I think when the power came back to the door, it spiked the BCM and knocked it out. Simply pulling #7, #22, #28, the 50A fuses in the engine compartment, disconnecting the battery individually, did not work. Maybe it was coincidence, but #7, #22 & #28 TOGETHER did the trick. EVIC back to life and EVERYTHING works! ...didn't have to replace the BCM, EVIC or PCM. It was a $0 fix.

Thanks for everyone that takes the time to post. Good luck!
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