13 hours ago, HS30-H said:

ECCS was first used on the 430-series Nissan Cedric in Japan (June 1979). ECCS stands for Electronic Concentrated (Engine) Control System.

Thanks for the clue. I had looked in the 1982 FSM and found the combined EFI and ECCS descriptions, letters only, but should have started at the beginning. In the first 280ZX use of the ECCS, the 1981 Turbocharged 280ZX, they created an ECCS-only Supplement chapter, where they actually used the words, as defined above. Image below.

They do call it a "micro-computer" in their description. I'm still not sure though that it does computing, in today's sense of computing. Besides the fact that it's not digital. (Sorry SteveJ, now that's really pedantic, Just having fun.). But it was still early days for computers, and I think the definition still varies today.

From the 1981 Turbo Supplement Engine Fuel chapter -

2 hours ago, Zed Head said:

They do call it a "micro-computer" in their description. I'm still not sure though that it does computing, in today's sense of computing. Besides the fact that it's not digital.

I've been inside a non-turbo 83 ECU, and it was, in fact, computer controlled. They were running a Hitachi 6801 embedded controller. And even though I've never personally been inside the turbo ECU, I am nearly 100 % confident that it would also contain a microcontroller as the turbo required much more control than the NA version.

So yes, the later years were digital, and computer controlled. Don't know when they made the switch though.

But what do you mean by "computer"? Does the controller contain a program? Does it perform computations? Or does it just convert one electrical input in to another?

I don't know. I found some interesting things about it. It looks like it does contain programming, I wonder how complex it is. It would be interesting to see some of the code with comments. I assume that the code/program would be considered digital but the inputs and outputs not.

https://www.cpushack.com/2017/12/07/cpu-of-the-day-hitachi-hd6801s0pj-automotive-6801/

http://www.bitsavers.org/components/hitachi/_dataBooks/U24_Hitachi_6301_6801_Assembler_Text_Editor_Users_Manual.pdf

So, going backward from 1983, do you know when the Hitachi controller was introduced in to the ECU's? I know that the FSM's say that the 1979 and later ECU's cannot be plugged in to 1978 and earlier systems, even though they use the same connector. The pinouts are different, maybe because 1979 and up contain the controller. Does 1979 contain the controller and 1978 does not?

Referring to what HS30-H said above, maybe the controller was introduced in to the ECU's also in 1979, along with being used in the ECCS.

Only commenting to learn some new stuff. I started watching repair videos for modern vehicles and learned that they have all kinds of modern tech with high speed and low speed communication networks, and numerous "modules" each usually with its own controller, communicating on the networks. I think that even the intrument cluster in my truck has its own controller. Crazy. Always something new to learn...

I found an old thread that might have some pictures. Haven't gone all the way through it. Funny though, Nissan uses the word "compute" in describing how the ECU (1978 I think) sets the injector pulse length. It's on page 3, post numbers are gone.

Edit there's only a few pictures of early 280Z "ECU"s.

Edited Monday at 02:05 AM2 days by Zed Head

Usual pile on... I found what is supposedly a 1979 280ZX ECU on the internet with some good pictures. I don't see a 6801. Maybe there's an earlier controller in there somewhere? I'm not an electronics guy.

The guy has a nice web site. If you click on the picture you can scroll through all of them and blow them up to a good size with another click.

https://www.importapart.com/product/79-datsun-280zx-2-8l-l28-ecu-ecm-pcm-engine-computer-a11-616-420-oem-1869/

Edited Monday at 02:29 AM2 days by Zed Head

More piling. Sorry, but now that the original question has been answered I'm just following this new thing.

Edit - there is a lot in this Hybridz thread. Answers some questions. Way beyond my skill level, couldn't even try to fake it. Just curious.

HybridZ

re-mapping and live tuning L28ET 1982/83 S130 ECCS

Edit for latest information; See posts further down for full details on modifying 1982/83 ECCS for re-mapping and live tuning. All information related to reproducing this project can be found on Gi...

Edited Monday at 02:40 AM2 days by Zed Head

On 4/21/2025 at 4:28 AM, Zed Head said:

I found what is supposedly a 1979 280ZX ECU on the internet with some good pictures. I don't see a 6801. Maybe there's an earlier controller in there somewhere? I'm not an electronics guy.

Hi, quite a stir i made hihi... A 1979 eccs is without any microprocessor, i can tell you as a electronics engineer.

Those round tin boxes (with cooling crown) are early integrated circuits, nice to see! Later on the plastic black boxes came. (Some are already on the printed circuit) The 6801 is a microprocessor and works with 0 and 1 signals of 0 and 5Volt.

As far i know the switch was made between 1982 and 1983. Then analog "computing" became Digital computing where real microprocessors took over the work.

I don't know for the USA But overhere in europe the 1983 280zx turbo was the first z with real processor in the managementsystem. (Europe never had a 280zx turbo before 1983!)

All those boxes in 280z and 280zx were called ECCS until the 1983 turbo came out. (I belief..)

(Don't hold me to it, i'm not a wizard, just remembering this stuff..) ;-)

Edited 9 hours ago9 hr by dutchzcarguy

I found an old thread with several of us iin it. I feel kind of dickish reading my old comments. Hopefully I've mellowed. The 6801 has come up before, I'd forgotten about it.

I also pulled up the 79 and 83 EFI ECU wiring diagrams and they seem essentially the same. Odd though that the 79 diagram doesn't show the O2 sensor circuit to the ECU. Just interesting that they apparently added the microprocessor to what had been a processor-free system.

1979

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1983

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