406 Electrical Problems

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Spriteracer
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406 Electrical Problems

Post by Spriteracer »

I will apologise in advance for the length of the post, but all these problems may be linked, so I have included them all.

I have a 2002 406 HDI.

I have only owned the car for a few weeks, but it already appears to have a few gremlins.

When starting off from cold, with the lights on, the headlights seem to go dim when I change gear. This only seems to happen for the first mile of travel. It is the sort of thing you would expect from a slack alternator belt, but this doesn't seem to be the case and, obviously, it seems a little odd that it should only do it when cold.
I'm not exactly sure how the headlights are connected as there is an 'automatic' option - which I have turned off. I like to be in control of my own destiny! But there does seem to be a slight time delay - half a second, or so - when switching the lights off, so I'm assuming some sort of electronic control.

Last weekend I decided to liston to the F1 Grand Prix on the radio, so switched to medium wave. I was driving with the wipers on at the time and I believe I switched to intermittent/auto. A message appeared on the display saying "Automatic wiper operation" or something. Anyway, this message would not go away. I assumed it would go after a few seconds, but it did not. I tried turning the wipers off and pressing the end of the stalk to toggle the display, but it was still there. Eventually, I turned off the radio and it went.

The same day, I tried to start the car. It beeped and the message "engine immobiliser fault" appeared on the display. I turned the ignition off and back on and it started straight away.

A couple of days later, I returned home, turned off the ignition and the display panel stayed illuminated. I shut the door, locked it and waited for the interior light to go off, but the panel was still lit.
I turned the ignition on and then off again - obviously after unlocking the door - and the display panel went off.

The latest gremlin appeared yesterday. I filled the tank 2 weeks ago and the gauge has been gradually falling until had reached half-full. Yesterday, it suddenly went up to three-quarters!

I have a printout of the service history and it has had 2 repairs in the last 18 months for "interior gauges/wiring" - whatever that would be?!

Not knowing which black box controls what, I'm hoping for some help!

I'm beginning to think that modern cars are somewhat over-complicated...and they used to call Lucas the Prince of Darkness!!

Any ideas?
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fastandfurryous
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Post by fastandfurryous »

This, I believe is a multiplexed car.

Other people on here know more about the system than I do, but this sounds like there is a bit of a communication problem between the BSI box (which controlls EVERYTHING) and various components.

It will probably be fixed with a software update or similar.

I'm afraid to say that if you like to be in control of your own destiny, then you're in the wrong car. Every single aspect of the operation of a multiplexed car is electronically controlled. The BSI is in control.

(OK, that's somewhat of an over-dramatisation, but I personally do not trust multiplexed cars.)
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Spriteracer
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Post by Spriteracer »

If it is multiplexed, am I going to have any problems connecting the wiring for my towbar?
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Post by PowerLee »

Hi

Yes this 406 is multiplexed.

Do you have a cd changer in the boot?

If it has I bet the rear lamp seal has leaked water in :wink:

Has it had a software update lately?

Do you have both of the keys & the blue plastic security code card?

The slight delay on the electrical front is normal, Its just the way plexed cars are.

The normal electrical functions, lights, horn, climate control, radio etc run at a slower speed.

The safety systems, SRS, ABS etc run at the fastest speed & take first place when being sent down a CAN signal wire.

If you have a cd changer then checkout the rear lamp seal leaking, That is a classic 406 expensive multiplex cock up waiting to happen :wink:

Get water in the cd changer & the multiplex system will go & have a major sulk.

You might need a new COMM 2000 unit, Peugeot have been very nice to people & held there hands up to the COMM 2000 design fault & stuck a 4 year warranty on the original COMM unit that came with the car.

You could always try a reboot.

Make sure the alarm is disarmed, Dont worry about the radio code, Its plexed so you dont need it :wink:

Disconnect BOTH battery terminals.

Touch the two metal ends of the battery leads together for a few seconds to discharge the stray electric from the multiplex system.

Reconnect the battery.

Wait at least one minute.

Lock & unlock the car.

Open the door & turn the igntion on.

Yes you could have problems with a towbar, But ONLY if the person fitting it doesnt understand about multiplex / CAN systems.

Either find a tow bar fitter who does ( yes there are some out there ) or get a Peugeot main dealer to fit it.
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Spriteracer
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Post by Spriteracer »

Wow, this is sounding interesting.

I don't have a CD changer, just a single in-dash unit.

As the problems seem fairly intermittent/sporadic, I thought I may be looking at dodgy connections somewhere, but it's knowing where to look.

I don't know if it has had a software update, as I have only recently bought it. How often do they need to be updated and what does it involve?

I do have both of the keys, but no blue plastic security code card. Assuming I could possibly get hold of it, what would I do with it?

What and where is the COMM2000?

If I try the reboot option - seems like a reasonably simple start point - how do I disarm the alarm?

I was planning to fit the towbar myself. I have heard about bypass relays for multiplexed cars...is that what I'm likely to need?

Finally...phew...I have seen various CD workshop manuals on Ebay. Does any know if they are any good?

Thanks
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Post by pugxpert »

i would check your cd player or its connector if no cd player fitted behind left rear light,water gets in through rear light then into connector or cd player and currupts data messages on data/data bar wires,when your instrument panel cant communicate with bsi it goes into downgrade mode which is all warning lights on,illumination lights on and oil level gauge flashes along with a few other things,also if your cd is dry check wiring harness connections under carpet in drivers footwell,this is a favourite place now if it has had a new windscreen and not been bonded in properly and letting in water. dont worry about getting a software update for your bsi as 406's could never be downloaded,any upgrades had to have a new bsi as the memory is not a re flash type. only upgrade i know was for early multiplex versions with a low oil level fault. as for your headlights dimming ,i would check battery voltage,i remember most of them dimming slightly after start up when a/c on and post heat on the glow plugs,a lot of load out of battery and alternator ,if not that bad i would not worry about it. but a new car battery if yours is old may improve things..
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Post by acataldo »

Hi,

I was ready the post because i am have electrical issues with my 406 HDI (T reg 1999 90PS).

I blip the central looking and I see the dails on the dash move, I turn the ignition to position 2 and I get no bulb check/STOP light, ABS fault bleeping on the centre LCD display & no odometer reading. Try to start and I get a poor cranking speed and it can take a long time to start. While I am driving, the dash has a mind of it's own and the radio can cut out when apply electrical load (electric windows etc..). Obiviously these faults are intermittant but are more frequent after a long soak (i.e first thing in the morning).
Antonino
Peugeot 406 GLX HDI90
Peugeot 405 GRDT
Peugeot 205 GL 1.1
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