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-   -   Werd Electrical Issue (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/werd-electrical-issue-1130550/)

grinder 10-05-18 02:06 AM

Werd Electrical Issue
 
Good morning from across the pond :)

Ive not been on here for 5 yrs according to my last log in time ;)

I have a very strange electrical issue with my JDM S5 TII Cab Auto

She has been stood for a good 3-4 years so decided to fire her up and see if she would run , so plugs out , some 2 stroke in the chambers and she fired right up and settled into a idle .. and this is where the fun begins :)

She has a broken auto box and I need to sort it out , but I have some electrical issues ( we will ignore the box for now )

All the external lights work on the car , but I have no lights on the idiot cluster box ( thing where the clock is ) and nothing on the dash ?

The indicators work ( turn signals ) but they don't flash up on the dash

The hazard lights work externally , but don't flash on the dash

Im not sure , but I "think" my actual dash back lights aren't working either - I will check this when I have 2 mins spare

Low beam and high beam work - but no indicators on the dash

Rev counter work and boost gauges etc...

Now the auto box is stuck in park , so wondering if its not getting a signal from the brake pedal .. but then you press it the brake lights light up at the rear

I have the "P" indicator on the dash .. so its getting a signal from somewhere

I checked the room fuse and that seems fine ( checked with a meter ) and all the other fuses seem OK to

The windows work and so do the mirrors

The heaters work but the radio doesn't

Im just in the process of selling my other FC3S so it would be nice to get this car back on the road .. but with these electrical issues , I'm not sure if I can

The car has a turbo timer , and that seems to be working just fine

So either I have bad power , or a bad earth somewhere .. does anyone have any idea where I should start to look first ?

I also have ONE headlight that wont "park" correctly … not sure if that has anything to do with it

So in a nut shell .. put the key in and just prior to cranking , I have NO lights in the idiot cluster :(

Sorry about the long post , but thought I would try and get as much info down as possible

Everything I have read points to the meter or the room fuse , but I have swapped these and tested with a meter and they seem OK

I swapped out the headlight switch a few years ago and ran a new 12v feed to it - so I can only assume that it is working as it should be

Thanks for reading

Stu

professionalpyroman 10-05-18 06:04 PM

As far as the dash illumination goes, have you checked for voltage at the connector behind the gauges? The pins on the circuit board are labeled.

grinder 10-06-18 06:41 AM

to be honest I haven't started ripping it apart yet .. I've just checked the basics like fuses

I didn't want to start to remove the dash etc.. to find it may be a common relay or ecu issue etc..

Hot_Dog 10-06-18 07:36 AM

>>> I have NO lights in the idiot cluster

I would recommend checking and/or replacing your CPU located at driver's side kick panel.

grinder 10-07-18 05:21 AM

to be honest , that's what I was thinking .. just need to locate one now :(

Any idea if the JDM is different from UK/USA ones ?

mazdaverx713b 10-07-18 06:42 AM

The FC's suffer from cold solder joints on their electronic components. The CPU controls the warning light cluster's functions and it sounds like it is suffering form cold solder joints. I would remove the CPU and either re-solder it yourself or have someone do it for you. This is the standard fix and it will work like new when re-soldered.

Hot_Dog 10-07-18 08:31 AM

>>> Any idea if the JDM is different from UK/USA ones ?

Don't know.

If you're handy with a soldering iron, than you might want to first replace the electrolytic capacitors (since they usually leak) and check all the other solder joints for poor quality. This might save you a few bucks.

grinder 10-07-18 10:35 AM

I wouldn't have expected the CPU to effect the radio though … or the dash board back lights .. although to be fair im not 100% sure what it DOES control :)

so would the CPU stop the indicator lights in the dash working ? ( based on that they do work externally on the car )

When I get chance ( could be months off in real terms as real life gets in the way ) I will remove the CPU and have a look .. im pretty sure I have some contact cleaner in the garage so will give it a good going over with that too :)

Hot_Dog 10-07-18 03:26 PM

>>>> so would the CPU stop the indicator lights in the dash working ?

Probably not, but who knows. When these cars sit for long period of time the electrical system seems to go to crap. Case in point, in 2002 when my S5 blew an engine and sat 6-8 months until I decided to revive it with a Mazda reman. Once I got it going again the electrical system seemed to have gone to hell. I mean, some things worked and other things didn't work. After awhile, everything cleared up and worked fine. Bottom line, when these cars sit for a long period either the electrical connections become corroded or the electronics components such as capacitors bite the dust.


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