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MrDan22

New Member
afternoon people, i knew it wouldnt be long until i required help.

After a short drive (less than 5 mins) to pick the missus up i noticed all my lights flashing on and of on the instrumnt pannel and all the gauges intermitently working, i chanced it and continued the drive home the lights n gauges came back briefly and the temperature had sky rocketed into the red.
I've only recently brought the car so i'm hoping i haven't been sold an old duffer:mad:
its a P38 1994 4.6 hse petrol/lpg
before it happened i took the old non working stereo out to check the plugs in the back but all had been chopped and tapped up, could i hav shorted something?

took a video to see if that would help ppl diagnose the prob :mad:
https://www.youtube.com/watch?v=2xXXVQJR5Rg&feature=plcp
 
Sounds like your alternator is playing havock with your instrument panel get battery and alternator checked or like you say s short is occurring secure all loose wires
 
i think its had a new alternator, n battery from the previous owner but i will get it checked.
where would i start searching for a bad earth? and if it is a short would it still have to be shorting out for it to be flashing?

i haven't had this car long at all so im not to clued up on it all.
cheers for the quick responses!
 
Follow where the battery goes from the battery to the driver side air bag housing down to above the sump bolted to the engine block .Not sure what you mean by flashing all bulbs or some? Make sure all wires are taped of have plastic connector blocks on ie no bare wires
 
Intermittent gauge cluster is classic signs of failing alternator esp tachometer. Suggest hooking a voltmeter onto battery to check output under load at 2000rpm. Should be 14.4 ish
 
i'll check everything asap and get back to you and let you know what i find. its much appreciated!
i just hope its not too serious.
Regards
Dan
 
I would suspect a dodgy earth causing a leakage somewhere....

Check the under seat fusbox for security too, as the flashing panel lights are fed from Fuse 1 and the interior lights (which some dash illumination lights and the HEVAC lights use) is Fuse 15(?)...check these for security....

Definatly a a leak somewhere
 
Check the under bonnet fuse box for sign/smells of burning and for tightness of the positive lead connection, also check the connections are tight and clean on the battery and alternator. The concensus is that the charge voltage should be around 14.2 volts on the P38.
 
afternoon,
i'v had a look around with my voltmeter and the alternator and battery are ok, i checked all the fuses n they are ok except one i get a 12.2v reading off the instrument panel fuse under the drivers seat. at fuse F1, is this correct?

*this is with the ignition off
 
Last edited:
F1 if the Instrument pack yes....

When you say you get 12.2V....what is the battery voltage in comparison??

If the Battery is say 12.8V and you are getting 12.2V there could be a leakage somewhere due to a bad earth, or a short somewhere dragging the voltage down....

I am not an electrician so only speculating.....

I would hazard a guess that the volt drop from Battery to Fuse board is negligable so I would assume Battery Volts should be present at all points unless there is a short or leak!!
 
Volts don't leak unless the voltage is very high, a short would burn something, so a high resistance connection if there is a big difference between battery volts and F1 volts, or a broken wire giving intermittant connection.
 
Fuse 1 is feeding a few things. Key illumination, Clock, Radio, Etc so you will have a slight voltage drop. It should rise a little with engine running.
 
Saint.V8 said:
F1 if the Instrument pack yes....

When you say you get 12.2V....what is the battery voltage in comparison??

If the Battery is say 12.8V and you are getting 12.2V there could be a leakage somewhere due to a bad earth, or a short somewhere dragging the voltage down....

I am not an electrician so only speculating.....

I would hazard a guess that the volt drop from Battery to Fuse board is negligable so I would assume Battery Volts should be present at all points unless there is a short or leak!!
Click to expand...


In comparison the battery is 12.35v
 
when the engines on and revving at 2000 ish rpm (got no dials) its out put is 13.18v and no change in voltage from idle. the alternator and battery are new (from what I've been told by the previous owner) so could it be an under powered battery or duff alternator that's causing the intermittent dials?

And is there a way of ruling this out? such as hooking up another batt?
 
MrDan22 said:
when the engines on and revving at 2000 ish rpm (got no dials) its out put is 13.18v and no change in voltage from idle. the alternator and battery are new (from what I've been told by the previous owner) so could it be an under powered battery or duff alternator that's causing the intermittent dials?

And is there a way of ruling this out? such as hooking up another batt?
Click to expand...

Voltage is fine ish?? what happens to it with everything electrical turned on. if it drops quickly Alt is fooked if it drops slowly battery is fooked if it dun't drop both are fine..
 
redhand said:
Voltage is fine ish?? what happens to it with everything electrical turned on. if it drops quickly Alt is fooked if it drops slowly battery is fooked if it dun't drop both are fine..
Click to expand...
Agreed as said you need to drop charge test the battery , it's no good just putting a multimeter on it you need to see how it cope under strain .

I'll give you an instance my idler pulley/ tensioner was pretty shaged enough to let the alternator slip a bit causing all sorts of havoc with my dials.

You said earlyer about a relay swap it there is plenty to choose from if you think it is duff.
 
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