Excellent Code Reader

Richard Gallagher · Post by **Richard Gallagher** » 11 Dec 2003, 04:32

There has been quite a lot of discussion about code readers on this forum recently, hopefully I can now shed a little more light on the subject. My 2.0 turbo Xantia has been suffering from a slight misfire recently and having done the usual checks of plugs/leads, compression, resistances on various electrical items etc. I decided to splash out on a 'proper' code reader namely a Sykes Pickavant rather than a Gunson LED one. When plugged in to the car no fault codes were recorded within the ECU, but what this reader does is also display the information being <b>received</b> by the ECU down to air intake temperature, length of time injectors are operating for, coil recycle time, air con status, the list is almost endless (and quite interesting if the TV schedule is boring!) The benefit of this is that on one test it showed the voltage at the throttle poteniometer and lambda sensor to be fluctuating quite wildly, even though a resistance test showed no fault on the throttle pot. So, with these two items being closely linked (cause and effect) I have just fitted a new throttle poteniometer and whehey engine now sweeter and voltage constant.
So its fair to say that I'm quite pleased with my new toy but it just goes to show that if the 'senor/actuator' is working within perameters no fault code will be triggered, but if the <b>machine operator</b> delves deeper, then faults can be found.
Interestingly when I put it on my other Xantia 26,000 miles 2 faults are recorded and on my Picasso three, not bad at only 3,000 miles and having just been dealer serviced!!

AndersDK · Post by **AndersDK** » 11 Dec 2003, 05:07

Richard -
I'm aware that my lovely carbed '89 BX16 will not last forever - and my next "new" car will most definately have injection & ECU fitted.
What is the typical retail price of this wonder ?
I guess it covers a range of ECU models & manufacturers - rather than car models ?
- website to any dealer ? - even Sykes Pikavant website for detailed description ?
My bet this is interesting to lot's of DIY owners - as faultfinding modern engine management systems is a real nuisance - compared to the good old carby & dizzy engines.
(just look over my guessworks from the past year [:I])

Richard Gallagher · Post by **Richard Gallagher** » 12 Dec 2003, 02:48

Anders,
The website address for sykes is 'tools.co.uk' but a more informative site operated by them is 'spsmart.com' which delves deeper into this specific subject.
Basically what I did is to buy the 'base' hand held unit second hand from ebay.You then need the relevant 'pod' and harness to connect to the relevant car you are looking to test.
The total cost of the investment for me is about £200, not cheap, but for me personally, worth it.
The equipment is expandable to cover a very wide range of vehicles by purchasing more pods and harnesses which also allows it to be kept up to date as new vehicles and systems are released.

wheeler · Post by **wheeler** » 12 Dec 2003, 02:55

when checking the paramiters of a (upstream) lambda sensor when the car is warm (ie in closed loop) it SHOULD fluctuate constantly,it fluctuate between approximately 100-800 mV.
Faults registered in your other cars are nothing to worry about if there is no complaint with the car or no engine management light on,they may just be 'phantom' faults.
*Edit* should have said upstream sensor.

AndersDK · Post by **AndersDK** » 12 Dec 2003, 03:24

Definately looks like a "smart" handy tool.
Obviously some "crackers" may allready know how to read off the information directly into a PC.
My bet that next generation of this tool is purely cable harness hooking up to a PC - the rest would be any appropriate software program displaying the info on screen.
Tx for the links Richard.

wheeler · Post by **wheeler** » 12 Dec 2003, 04:58

Which ECU's can it read on your picasso Richard ?

lhm_leak · Post by **lhm_leak** » 13 Dec 2003, 03:21

Anders, it's definitely possible to get the data into a PC. All you need is a simple level converter, and a minimal amount of processing power to deal with some of the awkward baud rates and control lines that can be involved. I looked at this a while ago, using a Motorola 68302 multiprotocol processor as the core - but it turns out that this is overkill (has at least as much processing power as early ECUs themselves!) and could probably be done by something like a 68HC11 or even a PIC12C508 for a lot less money. I'm looking at this project now, with the intention of producing a design that's simple and dirt cheap. Most of the implementation will be in software, and I'm looking at doing this for PDAs and certain mobile phones in addition to traditional PC stuff. I must stress that I'm not doing this for profit - It's an interesting technical challenge for me (an engineer with 18 years experience in software and embedded systems design) and I would welcome input from anyone with any relevant experience - also from end users with regard to features etc. that they'd like to see on such a device.
Makes a nice change from the oily stuff, anyway. My Xantia TD has decided to create another big green puddle - but that's another story...[}:)]
Stu.

AndersDK · Post by **AndersDK** » 13 Dec 2003, 07:43

Well Stu - as I suspected [;)]
As you can read from my first submission on this topic - I have not yet hands-on experience with these DIY monsters.
Being in electronics engineering myself since the 70-es - and with some embedded CPU work in the past - this also challenges me [8D]
- and I'm definate that a specie of the PIC16 family would make this an easy job - since this family is ever growing with all kinds of features added - being so simple to program.
At present there some very basic functions I don't have a clue on to these engine management systems :
1) do they return purely digital info (any odd baud rate & protocol)
2) do they use any standard logic levels/protocols
3) do they in fact have a separate analogue info line (sensor values)
In the past I spent 1.5year on a project - "listening" to the communication protocol used by enclosed Digital Corp computers for macinery - and from info gathered I programmed a communication module with user interface running on a standard PC (simply running DOS) - to communicate with these Digital's.
Back in the 80-es this was still an economical project - since any added software modules for these Digital's was so darned expensive.
Besides that - this "world" of Digital was so different from the standard PC environment.
This project was the onset of a later huge network for all machinery employing Digital's in the company - making production machine programming so much simpler & cheaper.
Off topic ? - not at all - let's kick those smart code readers off the market [}:)]

arry_b · Post by **arry_b** » 13 Dec 2003, 16:22

Hey Anders, I've got a PDP-11 running DSM in my basement with a LA100 hardcopy console - fancy making an ECU reader from one of those?

AndersDK · Post by **AndersDK** » 13 Dec 2003, 18:07

[:D][:D][:D] ... hehehehe Arry [:D][:D][:D][:D][:X][:X] ....hehehe
PS : why is it that so many IT/electronics engineers drive hydraulic Citroens ???

lhm_leak · Post by **lhm_leak** » 13 Dec 2003, 19:15

To answer the last question first, we probably drive hydraulic Citroens because we like the technical challenges involved and are not afraid of the complexity! Agreed on your sentiments regarding kicking "rip-off" code readers off the market - my basic idea is for an open, extensible project that'll do to the motor servicing industy what Linux is busy doing to Microsoft. I'll gather my thoughts and data and stick them on a web page somewhere as there definitely seems to be considerable interest in this. I'll post a link when I've done it.
To get a bit more technical, a PIC16 will definitely work - I've been sent a link to a page describing just such a device, but it's not really what I'm looking to create. All I need is a protocol converter, and a "lesser" PIC12 series device is probably adequate for this. To answer your specific questions, it's 1) Yes, 2) Sort of, 3) No. Obviously the number of ECUs I've come across is very limited, and more input is needed from those "in the know" in order that the proposed device can cover as many vehicles/functions as possible with just a cable change.
Stu.

AndersDK · Post by **AndersDK** » 13 Dec 2003, 20:41

Tx Stu -
- now I'm prepared using my good old DOS based serial communication "sniffers" - packed down with good old ".arj" - on an ancient CD somewhere in my office [:D][:D][:D]

lhm_leak · Post by **lhm_leak** » 14 Dec 2003, 05:23

Yes, I've got a good old DOS analyzer for serial comms - still use it most days, since my current work projects involve lots of serial data!
Just went to upload my first attempt at a webpage, and my server wouldn't accept my FTP connection. I'll try again tomorrow.

lhm_leak · Post by **lhm_leak** » 16 Dec 2003, 03:33

It's done now. The address is in my signature.