Wiring in a digital clock to an older loom

[Ped]

I have been experimenting with fitting a digital clock from a later (1984) ZX to my earlier 1980 280zx.

The gauge unit is the same for both models, but the older dials PCB has 2 connector points taped over (A & B). On the newer dials these are to take an additional 2 wires from the digital clock.

I assumed it would be a straight swap, but on closer examination there is a wire absent from the older harness connector block (Yellow/Red on point 4 of the connector according to the Haynes manual). Other than this I think the wiring is exactly the same on both models.

Should I...
1) "Leave it alone you fool, you'll fry it!"
or
2) Call an auto electrician.
or
3) Wear a watch instead.
or
4) Find a suitable point in the wiring to connect into. This is where I need a bit of informed advice. There seems to be a Y/R connection at the front speaker (according to the Haynes manual), but I don't know how accurate these are for European spec. Any thoughts...

 

[ollyc]

I'D GO WITH, 1, 3, 2, and then at least if it does start knackering things your a little more covered than blowing things yourself. I must say I had a horrific time fitting a new amp and headunit in my 83 zx but I think that may have had something to do with the previous restoration people. wiring was not as should be so stripped back and replaced it. But I'd get an auto tech in and at least paying him will instate his insurance. Good luck matey and keep us updated. if you figure it out let me know as my bloody clock don't work either!!!!!! Lol

 

[Ped]

I think the analogue clocks bearings pack up, not surprising after 25-30 years or so. You are probably right, it just seems to be one wire to connect, so seems a shame not to have a go, but I would probably regret it!

 

[ollyc]

Yeah in my experience it's that one wire that ends up costing a whole lot in time and money. So if you are going to have a go may I suggest fitting an in line fuse of a lower volt so if there is a prob it will blow a bit quicker. I've used this method a few times. Tut bearings that only last 25-30 years I don't know just not good enough Lol!

 

[A2Z]

I would see if the company at this link can help: ZClocks

 

[mick280]

No problems here. Just remove the old "assembly" and fit the new "assembly". You do have the complete new assembly (whole unit removed from the donar)? If you have, its just a simple matter of unplugging old and fitting new, no jumper wires to refit etc. I've done this before with no concerns.

 

[JEZ 280ZX]

Hi,
I've got the digital clock in my 1982 car, but I prefer the look of the analogue style clock.
The digital clock acts as a stopwatch/lap timer too....But I haven't figured out how you work it!?

When I changed the cassette player for a cd player, there was an horrendous bundle of snakes behind the dash, where a previous owner had removed the stock radio and fitted the cassette player and botched the wiring!

 

[Ped]

I would see if the company at this link can help: ZClocks

Cheers for this, looks interesting.

 

[Ped]

No problems here. Just remove the old "assembly" and fit the new "assembly". You do have the complete new assembly (whole unit removed from the donar)? If you have, its just a simple matter of unplugging old and fitting new, no jumper wires to refit etc. I've done this before with no concerns.

The loom is different than on a later model as described. I did try a staight swap then....

 

[Ped]

Much, much, much later… and I finally got round to seeing if I could get the digital clock working on the Zed. I was nervous about frying something, but have now resolved it, and it works!

Here is how I did it, but if in doubt contact a professional auto electrician.

First I bench tested the digital clock to make sure it works. I found a note on how to do this on http://www.zcar.com/forum/10-70-83-...2-280zx-turbo-clock-not-working-how-test.html. There was also some info here http://forums.hybridz.org/topic/71972-280zx-digital-clock-in-a-280z-jeco-quartz-clock-housing/.

Basically you connect the Black to (-) and the other 3 wires to (+), I used a 9v battery which is fine for this purpose. This should light up the digital clock dimly (as if the headlights are on at night).

You can see how it looks fully lit up by disconnecting the Green/White

So the clock works.

Here this is how the duff analogue clock is connected to the loom in my Zed.

This is the connector block that attaches to the back of the gauge cluster. Note that none of the wiring diagrams for any year matches my loom. No idea why, it all looks original and untouched.

Here is how I worked it out. Black wire and Blue/White wires are the same as the analogue clock. The Green/White is fine too (this is what dims the display with headlights on)… so it's just the Red/Blue I needed to hook up. First disconnect the (-) battery terminal.

I had a correct female pin left over from the mirror conversion I finished recently, so I crimped a new wire onto it and fitted it to the connector block at point 4 (I could have just disconnected the Blue/Red spade connector from the back of the gauge cluster and used a spade connector to attach the new wire to it). Then I connected this to the Yellow/Red wire (accessory power) on the green connector block near the fuse box. I tested it first to make sure it would work.

Re-attach the battery terminal.

All works fine. Note the clock only comes on when ignition key is on.

Finally as a note of caution, while messing about at the start trying various other points to connect into somehow my volt meter stopped working, ie: the centre dial of the three. I had a spare and swapped it out and everything now works fine.

So if in doubt call a professional, and proceed with caution.