Any E38 Experts on board? Electrotrickery Issues

[83C]

Over the last few weeks my E38 728i has suffered a few weird electrical gremlins.

 

First the windscreen washers partially packed up - when I pull the windscreen wiper stalk for wash/wipe the washers jet out water for half a second and then die. The wipers work normally.

 

Second the main beam headlights come on and off randomly when the headlight/indicator stalk is in the dipped beam position, and stay off when the stalk is in the main beam position.

 

This morning the third fault appeared - leaving home the car drove around 600yds and then went into limp mode - the message on the dash was 'Fail Safe Mode'. No engine management light, all fluids present and correct. I switched it all off and started it again but it immediately went into limp mode. It revs to around 1500 and that's it, and the revs are lumpy, though it's smooth when idling.

 

Any ideas? I'm scouring the Meeknet E38 site too for a possible solution.

[83C]

Found this which might explain the washers and headlights but doesn't mention the throttle (fly by wire jobbie):

 

http://www.meeknet.co.uk/e38/Loom_fault.pdf

 

Anyone know if the wiring for the throttle is also in the same bundle?

[BavarianRetro]

First place to look for apparently random electrical faults on an E38 is the battery.

 

Check for voltage and charging before assuming anything else. All of those - and many, many more can be caused by low battery voltage.

[83C]

Ok, I'm guessing it should charge at the standard 14.4ish volts?

[BavarianRetro]

Yes. Anything around or over 13.8 should be OK.

[83C]

Ok. I know the battery isn't that old but a new one seems to be around £60 so not the end of the world.

[83C]

Yes. Anything around or over 13.8 should be OK.

Charging at 13.93v from cold. Started fine, no warning lights on the dash.

 

Just tried driving it, went into failsafe mode after 200yds.

[83C]

This might not be helping:

 

 

[BavarianRetro]

No. That's not good. I assume it's engine failsafe as opposed to trans?

 

Have you read the codes?

 

This is invaluable.

 

https://www.amazon.co.uk/gp/aw/d/B011KSTC6I/ref=yo_ii_img?ie=UTF8&psc=1

 

You'd need the 20 pin pacman adapter too. It's about a fiver.

[83C]

Not yet read the codes, I ought to get one of those readers.

 

It's the engine failsafe rather than transmission. Checked the BCU compartment just to make sure it wasn't flooded, dry as a bone fortunately.

 

New hose ordered, £20 delivered.

[83C]

No. That's not good. I assume it's engine failsafe as opposed to trans?

 

Have you read the codes?

 

This is invaluable.

 

https://www.amazon.co.uk/gp/aw/d/B011KSTC6I/ref=yo_ii_img?ie=UTF8&psc=1

 

You'd need the 20 pin pacman adapter too. It's about a fiver.

Where would I get a 'pacman' adaptor?

[83C]

Just looked and there's a link that sells both as a bundle. Sorted.

[83C]

New hose fitted, still drops into limp mode so I guess the fault codes will need to be cleared.

 

Bugger.

[BavarianRetro]

What were the codes? Clear them. Drive it until it goes into limp mode and read them again.

 

If it's a facelift, you can do engine stuff from the obd2 inside the car.

[83C]

It is a facelift. Nov. 2000 built. Got a code reader on order from Amazon, was hoping to get away with not buying one.

 

Slow progress because I work away and the car isn't where I am. Next update will hopefully be in a week's time....

[BavarianRetro]

That wee Creator code reader will read engine and gearbox codes and real time data from the driver's seat. Anything else needs the pacman cable under the bonnet.