P38A Signs of a faulty BECM?

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The saga continues with this thing! Disconnected the battery and took it the plugs from the becm sprayed in some contact cleaner just in case there was a bit of corrosion there. Hooked everything back up and started her up. She ran lovely (still nothing working inside) i put in the radio code that i got today, radio works! After about ten minutes messing about with the radio there was a couple of clicks and a new set of faults came up. "Electrical fault" "fuel gauge fault" and "temp gauge fault" and the horn started going off. Even turning it off and taking out the key left the dash on and horn going had to disconnect the battery. This was the dash with engine off and key out!
You sure it was the horn and not the alarm sounder?
 
Sounded like the horn. It was a constant tone as opposed to an alarm yelp. I'm just wondering if some of the contact cleaner got in to the board, I've noticed it leaves like a white residue sometimes when it dries on a pcb. I sprayed a nice bit on to the plugs. on the plus side I met a friend of mine that I haven't seen in years who used to work for jag/lr and when I told him I'd bought a P38 the first thing he said to me was "do you really hate yourself!" then he handed me a brand new compressor that he's had sitting in his locker for years to take it away.
 
Sounded like the horn. It was a constant tone as opposed to an alarm yelp. I'm just wondering if some of the contact cleaner got in to the board, I've noticed it leaves like a white residue sometimes when it dries on a pcb. I sprayed a nice bit on to the plugs. on the plus side I met a friend of mine that I haven't seen in years who used to work for jag/lr and when I told him I'd bought a P38 the first thing he said to me was "do you really hate yourself!" then he handed me a brand new compressor that he's had sitting in his locker for years to take it away.
Not good contact cleaner if it leaves a residue. If the BECM was completely fecked, the car would not start, nor would the central locking work, the alternator charge light would not work etc etc.
 
Day 2 in the BECM household and things are not going as they should! Digweed took the BECM apart today and found that the cleaner he used yesterday had left a powdery residue all over the boards! And the new cleaner that he bought, even though it said contact cleaner, was for ignition systems and left a greasy residue after cleaning. He didn't take the chance and is going to get another cleaner tomorrow :(
 
Day 2 in the BECM household and things are not going as they should! Digweed took the BECM apart today and found that the cleaner he used yesterday had left a powdery residue all over the boards! And the new cleaner that he bought, even though it said contact cleaner, was for ignition systems and left a greasy residue after cleaning. He didn't take the chance and is going to get another cleaner tomorrow :(

Is the board not sealed with a sort of clear lacquer except for where the plugs connect?
 
Is the board not sealed with a sort of clear lacquer except for where the plugs connect?
There is something there which I reckon the first contact cleaner I used reacted with it. There was a white powdery residue left on it when I opened it today. While the cleaner I got today got rid of it for the most part it left a greasy film after it. It was only when I read the very small print that I saw it's really for cleaning distributor caps and the like, seals it from water ingress afterwards. I'll be getting a proper contact cleaner tomorrow, I'm raging that Maplin closed down here, it was very handy for things like this. Hopefully my hawkeye will be here too, tracking said it's finally in the country!!!
 
There is something there which I reckon the first contact cleaner I used reacted with it. There was a white powdery residue left on it when I opened it today. While the cleaner I got today got rid of it for the most part it left a greasy film after it. It was only when I read the very small print that I saw it's really for cleaning distributor caps and the like, seals it from water ingress afterwards. I'll be getting a proper contact cleaner tomorrow, I'm raging that Maplin closed down here, it was very handy for things like this. Hopefully my hawkeye will be here too, tracking said it's finally in the country!!!
Aeroclene 50 is the stuff.
There is a very poor conformal coating on the circuit board, but damp gets under it.
 
Got a fast drying wd40 one, only one I could find. Got everything back together and back in the car. Put the heart sideways in me when I tried starting it, turned over for a couple of seconds and then everything went blank! Turned out I'd forgotten to tighten the bolts on the battery clamps. Once I'd sorted that and got my heart back to normal she started right up. Still nothing working inside! It's like there's a disconnect between the engine bay and the inside. I'm looking forward to getting the diagnostic tool and see whats going on.
 
WD40 is not a great thing to put on any electrics (IMHO).
Its a water displacement/dispersant (parrafin) not an electrical cleaning agent.
YMMV. Your choice.
 
No worries. It was the best I could find at short notice. I used to get a really good Maplin branded one before they closed down :(:(:(
 
Your symptoms reek of an earth fault somewhere
You need to be checking every earthing point there is on the car.
I think they're listed in rave.
Unbolt them and check no corrosion.
 
+1 on what data said
 

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actually a fish oil based product i think and useless on electronics.
You're right on that. This is the stuff i used though. Although i had a mini heart attack when it just died cranking over! Battery clamps were loose.
 

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