electrical problems

[bostonwayne]

Hi this is my first post an I have a 1997 p reg 406 petrol estate which has 7 seats and we love. However there is a few electrical problems which I hope someone can help me with. First of all the speedo rarely works and when it works its never the correct speed,the mileage and trip meter though are correct, The rev counter mostly works but sometimes sticks at about 2500 revs. The fan for the heater rarely works but when it does it works for about a week then doesn't work for ages, The rear wiper stops working sometimes but always works again when I get in the car the next time. The cig lighter sometimes is still live when ive switched the car off and removed the key so when I plug my sat nav in it blows the fuse. I would like to fix these problems as we are going to go on a tour of France in the summer in it as we really enjoy the car and would like to fix these irritations so I hope someone can help. Many thanks in advance

[Welly]

First up would be the heater fan, this is likely to be a burnt/scorched electrical 'spade' connector at the fan unit itself. There's info on here somewhere with pics etc but it's an easy fix if you're fairly competent with basic tools/connectors.

Speedo will probably be a control box where the 'input' signal is converted to power the speedo needle - again quite common on the older models.

The cig light can be made to be live by changing the position of the fuse, you kinda move the fuse to the next position but others might be able to narrow this down more.

Overall these problems you list are fairly common and not a big deal.

[mjb]

The cig lighter sometimes is still live when ive switched the car off and removed the key so when I plug my sat nav in it blows the fuse

The fuse (which should be 10A) shouldn't blow. If the power adapter is working fine, then check for metallic crud in the lighter socket and give it a good clean. Getting it out can be a pain though - if memory serves you need to shove a finger in and twist the inner barrel anticlockwise about 45 degrees before lifting it out. It'll be stubborn on your 17 year old car though!

[Doggy]

Hi and welcome aboard.

Agree with what the others have said - the rear wiper is likely to be broken wires in the loom where it flexes as the tailgate is opened. They are fixable, (I patched my bro's '98 estate up), but it is fiddly.

[gumby6371]

Hi mate and welcome,

Not sure if petrol and diesel setup is different but well worth checking for dry solder on the back of your clocks as I had similar issues on my Mk1, there is a good guide on here which eludes me at present, will post when I've had a proper search.

The blowers do suffer with melted plugs, I still have a spare Mk1 blower in the shed if you're not too far from me?

The ciggie lighter is easy to swap if you can get the bugger out as already said, when you get it out check the spade connectors underneath. Might be sensible putting the fuse into the ignition on only position if its shorting somewhere, IIRC there are only 2 fuses that have the option, 1 for lighter and 1 for stereo so moving both wont hurt anything.

[steve_earwig]

Speedo will probably be a control box where the 'input' signal is converted to power the speedo needle - again quite common on the older models.

I suspect that only applies to ML5 geaboxes and that BEs don't have this. Any idea what engine you have there Wayne?

[Welly]

I just went to shift this topic over to the Electrical bit but got scared....can you do it for me?

sh*t, I gone done it

[steve_earwig]

Shhhhhh They'll think we don't know what we're doing

[bostonwayne]

thanks for all your replies the engine is a 2 litre 16 valve petrol, I will get on with all your suggestions on Monday when I have time off as someone said it will be the heater fan first then the speedo. It sound fairly easy even if its parts from the scrapyard I feel quite confident now

[steve_earwig]

Speedo will probably be a control box where the 'input' signal is converted to power the speedo needle - again quite common on the older models.

I suspect that only applies to ML5 geaboxes and that BEs don't have this. Any idea what engine you have there Wayne?

2 litre 16 valve petrol

I just checked the part's diagrams using engine code RFV (2.0i 16 valve 135bhp) and this box doesn't exist, so I guess this'll be a dry joint on the instrument panel It's always worth checking the connections first...

[bostonwayne]

I will get another from the scrapyard and swap it over then I will have a speedo that works. At the minute I am looking at the heater fan but something is holding it back I've undone the two torx screws and the unit comes out but something behind it is holding it in I will check back in a few minutes Thanks for all the help though

[bostonwayne]

Right the only thing that is keeping the heater unit in is the wire that goes to the heater dial I am trying to disconnect that now

[GingerMagic]

While you are there, see if you can find the resistor too - I think it is a sort of curved and finned silver unit on an early model.

Worth robbing one if you go to a scrapyard and use it to check your resistor in case its that that is faulty - saves 2 trips,,,,

[bostonwayne]

I cant get it out yet but there is a connector about a inch long with about 8 wires going in to it that is not connected to anything so maybe that's whats wrong I will go back out and see if I can get it out

[bostonwayne]

I have the heater unit out but nothing to be seen at the back at all just a connector with two wires going to the fan I think the best thing is to put it back together and get another unit from the scrapyard on Monday I will keep you posted