ECU information required

[Rhinoman]

The auto ECU controls the auto box so it needs a bunch of extra pins, the connectors are made by Amp and are a type commonly fitted to Japanese ECUs, the thicker pins are used for power signals and other higher current applications.

From the information that I could find the service box is just a bunch of terminals connected to the ECU wires, much like a Y-cable, you plug it between the ECU and the wiring harness and then place an overlay over the box, the overlay tells you which pin is which for any particular ECU. There doesn't seem to be much benefit over backprobing the ECU connector except maybe ease of access.

I didn't find anything in the code that did anything other than what is described in the service manual. The Bongo has been in daily use so removing the engine temp sensor for testing hasn't been an option. If you find anything curious then I will go back and examine the elevant section of code.

[widdowson2008]

I was under the impression that it was the ECU that controlled when the fans are switched on/off (still am actually), and if that is the case, then the ECU must have the operating parameters embedded (switch on and off temperatures). Thats what I was after.

I thought the ECU was a glorified input/output device - ie: a PLC device.

[Rhinoman]

I was under the impression that it was the ECU that controlled when the fans are switched on/off (still am actually), and if that is the case, then the ECU must have the operating parameters embedded (switch on and off temperatures). Thats what I was after.

I thought the ECU was a glorified input/output device - ie: a PLC device.

Thats correct. The ECU seems to work purely on engine bay and coolant temperatures, the actual temperature values are in the service manual. There is also some diagnostic feedback as well to check that the fans (fan relays?) are actually operating.

[Driver+Passengers]

Hi,

I've just sat and read through this thread (despite OH trying to get me to start packing away all the camping stuff), and having had similar thoughts myself on deconstructing the ECU I will a) read it again, and b) spend some time seeing where I can get to playing catch-up. I'm well impressed with the progress made so far.

I'll probably start by getting familiar with the uP instruction set myself and going through the .lst file. I don't expect to get very far very soon, but am considering what my winter project is going to be this year. No specific goals other than trying to maximise code coverage and learn more about the Bongo. This will be the first ECU I've looked at.

Regards,
Matt.

[Rhinoman]

I had a look through my stuff, here is a link to what I have:

http://www.rhinopower.org/ECUs/Bongo/docs/Bongo.zip

The disassembler I used was from the MAME project and is very crude, it disassembles everything - data included. Where the data doesn't disassemble it throws an illegal instruction message which helps to identify the data sections.
If you start from the reset vector then you can work through the code identifying data fetches (data sections) and subroutine calls (code sections). I have had a quick go at this already, see the text file.
The key to understanding the code is in identifying the inputs and outputs from the processor and then adding comments in the code, it then becomes easier to identify sections of the code that deal with the AT functions or the fan functions or whatever. The FSM describes most of the functions and the values at which things happen ie the temperature at which a fan switches on, although the information is scattered about a bit, when this information is added into the comments it should all become clear.
If you need any help ask.
Regards
James

[dandywarhol]

I had a look through my stuff, here is a link to what I have:

http://www.rhinopower.org/ECUs/Bongo/docs/Bongo.zip

The disassembler I used was from the MAME project and is very crude, it disassembles everything - data included. Where the data doesn't disassemble it throws an illegal instruction message which helps to identify the data sections.
If you start from the reset vector then you can work through the code identifying data fetches (data sections) and subroutine calls (code sections). I have had a quick go at this already, see the text file.
The key to understanding the code is in identifying the inputs and outputs from the processor and then adding comments in the code, it then becomes easier to identify sections of the code that deal with the AT functions or the fan functions or whatever. The FSM describes most of the functions and the values at which things happen ie the temperature at which a fan switches on, although the information is scattered about a bit, when this information is added into the comments it should all become clear.
If you need any help ask.
Regards
James

Rhinoman, I tried to reset a Vauxhall Vectra once and got into trouble. Feltching data wasn't one of my strong points and the submarine calls sounded like sonar to me. The S&M wasn't up to much and that's when I called it a day.

Apart from that, I understand everything you write about......................

[Driver+Passengers]

For reference, the receptacle for the '96 Diesel (non-ABS) ECU appears to be this one - TE 175448-6.

I've now got a set of plugs/cables (courtesy of ebygum32), so I will design a small inline PCB to tap-off all the signals with the aim of developing an inline diagnostic box o' tricks.

[Driver+Passengers]

For reference, the receptacle for the '96 Diesel (non-ABS) ECU appears to be this one - TE 175448-6.

Found PCB receptacle (and plugs w/o contacts) on eBay for $7 a piece, plus shipping. I've ordered three sets, totaling around £23, delivered. The set of plugs from ebygum have wires attached, so will serve to make up the first diagnostic harness. I should eventually be able to make a total of three, provided I can source contacts for the plugs, or obtain the plug set with wires from another couple of broken Bongos. Eagle PCB schematic and board layout in progress...

[Driver+Passengers]

Got 'em!

x3

[widdowson2008]

Got 'em!

x3

Brilliant.
Don't know if it's any use to you but I have ebygums ECU up for grabs. Had his permission to use for this sort of project. Could you use it?

[Driver+Passengers]

Don't know if it's any use to you but I have ebygums ECU up for grabs. Had his permission to use for this sort of project. Could you use it?

- thanks for the offer! I don't know what it'd do powering up with no sensors attached. I guess it could be used to prove the sampling circuitry, that's if there's any activity from it on boot.

I think I'll say not yet - I'll get the harness PCB designed, built and bench tested first.

[widdowson2008]

It's there if you need it.