Graphics interface for the 14CUX

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One of our clever American colleagues has been hard at it producing a graphical interface for the 14CUX that will run on various software platforms, and has now released it free for downloading. It does need a bit of hardware to be knocked together to allow you to interface a USB device to the rather odd OBD1 serial port on the 14CUX however. All covered here:


http://code.google.com/p/rovergauge/

http://alum.wpi.edu/~colinb/14cux_interface.html

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Alexdaredevilz said:

Looks to good and easy to be true?

Is it just a case of

http://uk.farnell.com/jsp/displayProduct.jsp?sku=1...

Plus plug adapter
400 ohm Resistor

And lap top?

That seems to be about it, plus you need the software to set the baud rate and handshaking orientation. That comes from the USB chip supplier.... not that Ive tried it yet.

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Harrytsg said:

Ok, so I've read (well, sort of) it all, and I have to say the pictures look great. i have no idea what the words mean though (except USB).

When can someone replace my dash with an lcd screen with this fancy stuff on it?

Not unless you build a laptop into your dash.

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I think the hardware would be around £25 to knock together, but to be honest the Steve Heath ECUmate does most of this without needing a laptop, it just plugs in and works if you want an idiot proof diagnostic that's easy to use and possibly loan out.

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blueg33 said:

Hi Mark

Saw your car at Neil Garner's yesterday, but didn't see you around. Your car still looks great

Nick

Nipped of for a while to look at all those aero / turbine engines in that "Bristol" museum. Still improving the car 20 years after buying it.....

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Alexdaredevilz said:

Looks to good and easy to be true?

Is it just a case of

http://uk.farnell.com/jsp/displayProduct.jsp?sku=1...

Plus plug adapter
400 ohm Resistor

And lap top?

That cable has a 3.3 volt output to drive the port, which is likely to be to low. It does mention in the blurb that the 1CUX will work with the 5 volt one OK.

I think this is the one from a UK supplier:

http://www.easysync-ltd.com/product/579/ttl-232r-5...

Edited by blitzracing on Sunday 8th April 19:59

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Alexdaredevilz said:

No offence Steve but the last fault code reader I bought from you was useless

I still got cold start issues and nothing comes up,

Used it on another's members car with differnt problems it came with nothing again, 2 weeks later he replaced the afm and it was fixed

Then a month later a new one came out

To be fair to Steve, its the ECU fault detection at fault not the reader. It wont pick up AFM faults where voltages are still present and varying albeit somewhat wrong. It also wont pick up lambda probes that are permanately dead, or lean / rich periods that might cause a poor idle, as the error condition gets reset the moment the probe starts switching again at some other point in the RPM band, so never gets flagged. To pick up fueling faults the probe first has to start switching, (this turns the lambda feedback system on) then either stick at 0 volts or 1 volt or more for some period before a fault is triggered. If it triggered each time the probes stopped switching for a few seconds it would be in fault mode all the time! You don't get any lambda readings on a stone cold engine, so no fault will show whatever the fueling is doing in the first 30 seconds. This is why the ECU mate has all the sensor readings, so we can use the grey stuff instead.

Edited by blitzracing on Monday 9th April 19:03

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Alexdaredevilz said:

Your dam right I don't know how it works,

That's why I bought it to try and find the faults, I wasn't aware it would only find some and under special circumstances

The afm problem was some one else's problem, so Im not going to go into that I just want mine starting up nice from cold

I did see your special offer, but there's a part of me that was thinking the more I spend trying to fix this horrible piss poor system(14cux) the closer I would be to replacing the whole thing

So far I've replaced or checked

AFM
HT leads
Spark plugs
Dizzy cap
ECU temp sender sensor
Timing
Compression
Fuses
Battery voltages and amps
Checked all wiring I can think of
3 Stepper motors and I'm 100% sure the current one I got works because I've seen it working on anther car
Air leaks
TPS voltages (fault 17 code did once flash up for 2 mins and then went)
Fuel pressure

I'm sure I've checked more I cant think of at the top of my head

Edited by Alexdaredevilz on Monday 9th April 19:25

So you have changed all this without actually what is going on then? You have assumed that a sensor input has failed in some way or ignition component, but what you really need to find out is why the mixture or ignition is wrong. Even something as basic as a colour tune would show you a highly over rich or lean mixture, or if you have the lambdas still fitted you can still use the voltage outputs whatever map you are running. If you want to take readings from stone cold you will need to preheat the probes with a separate 12 volts to the heaters. Although the mixture is richened for cold start, a lot of this is due to fuel condensing on the inlet tract and never reaching the combustion process. Once it gets as far as igniting you can still run Lambda one as far as the exhaust oxygen is concerned, so the ECU will pull the mixture back to this as soon as it gets a reading (Catalyst map obviously-). How has your CO trim been set up? Its perfectly possible to horribly overfuel or underfuel the engine if this is out at below 2200 rpm or so. Mine runs fine on a Mark Adams chip on the non cat map when cold, although it still runs a tad rich as far as lambda 1 is concerned, but it drives OK.

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Alexdaredevilz said:

I set the C0 trim as per MA

So far iv used a MA chip, 4.6 ecu and now a 5.0

The DC voltages are a basic set up only, Id beg or borrow a colour tune and try altering the CO trim setting, first when warm to ensure you can actually swing the mixture rich or lean (thats bright yellow burn for rich, pale blue for lean) What you want is darkish blue, with the odd flecks of yellow. (If the 5 volt feed to the CO trim is broken you wont be able to do this). If this works, then try it cold, and see how it affects the running. You need the right MA chip for the engine capacity to get the airflow scaling correct.

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what we saw there was the lambda probes stop switching and show rich at tick over, but it could be brought into range by raising the base idle, so it was not a million miles out. Ive seen quite a few TVR,s do this but I dont understand why raising the base idle alters the fueling- it should not, as the extra air also goes through the AFM, so the basic fueling should not change(??). B.T.W still got the colour tune?

If you think you have an ignition problem when cold, fire up the engine for just 20-30 seconds, and see if any of the exhaust headers are still cold with a quick dab with a damp cotton bud the hot ones will quickly dry. Anyway this is off topic.

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Bassfiend said:

blitzracing said:

B.T.W still got the colour tune?

Colourtune? What, one of those Gunsons things or do you mean your lambda sensor checker? ( I must get you to message me your addy again so I can pop it back to you... )

Phil

Just ignore me, I lent it to someone else with a cold start problem and have not got it back- sorry.

The Lambda test box is only good with hot probes, but if you where keen you could put 12 volts on the heater wires before you start the car so you got an instant reading and see what the box tells you, You would have to remove the 12 volt feed wire from the 14CUX into the Lambda connector and insulate it, and then poke a 12 volt supply in its place from the battery / ignition. At a guess you would need at least 30 seconds or more at 12 volts to get the probe hot enough. If you dont disconnect the 14CUX loom, the 12 volts will feed back down the loom to the fuel pump, and Im not sure how the ECU electronics would take it. I think a colour tune is easier.

I still think there is some mileage to be had by putting additional resistance across the temp sender to the ECU to make it think the engine is warmer than it is if you want to easily back off the cold start fueling. I guess now I have an ECUmate it would be easy to do, just pop a varible resistor across the temp sender and adjust it until I get the temp reading I want for a good cold start. It would not affect the high temp running, as the temp probe drops to a pretty low resistance when hot, so any (highish value) resistor in parallel with have very little effect.

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Back on topic, I have the USB / serial adapter now, and its not quite as straight forward as it seems, as you have to program the interface within the USB converter for the handshaking (this bits OK) but the baud rate is not so obvious if its non standard (as this is). I will find out how to do this and post it, but just to say its not just a case of connecting the adapter to the right plug with a 400 ohm resistor.

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It lives!

It did not take too much messing about in the end. Software wise, the USB to serial converter plugs and plays quite happily in both XP and windows 7. It will appear as a new com port in device manager when you plug it it, and you need to make note of the com port number windows assigns it (Comm 7, 8, 9 etc) to set up the Rovergauge interface. You also need to download the FT- Prog program and reprogram the USB device itself to invert the receive signal from the 14CUX. Its not difficult, but Im not going to go through it here. The baud rate is set by the Rovergauge software, wich makes things a whole lot easier than trying to get windows to do it for you.

The hardware really is dead simple, it just needs a TTS connector and a 400 ohm resistor as per the web site connected to the USB serial adaptor. As it says on the web site the TTS connector is not common place, but Ive found one (I hope anyway) from a Bentley parts supplier- apparently its an air con connector. I will look into getting a handful in so I can make more interface cables if there is a need.

Once I has happy the hardware was working, I plugged it into the loom, and fired up the Rovergauge. It refused to talk to the Comm port whatever I did on my Windows 7 laptop, but burst into life on an XP machine. You need to have the ignition on, then hit the connect button to get the communication started. I will query the Windows 7 issue with the guy who has written the software, to see if there any more clues on this one.

In terms of its use, its pretty straight forward, will nice clear readings on the gauges. It also shows the map you are using, and you can actually see the load points in the map changing dynamically,(This is a slow process- I though it would change really fast all the time) so it shows you the hex value directly as its seen in the Eprom. This could be very interesting if you are looking to change the fueling in the chip! I have not been able to read the level of correction the Lambda probes are applying to the map if its out, as my current set up joints the exhaust headers before the lambda probes, so the ECU cant correct the mixture as the two banks are joined upstream. I need to test this on a car with the cat map.

When you switch the igntion off it holds the last data received from the ECU,(which could be useful if you are chasing an intermittent fault) or there is also a data logging function, but Ive not played with this yet.

This is an excellent bit of software if you just want sensor readings, basic fault codes and mapping data, and makes a nice addition to the ECU mate in terms of its mapping data layout.

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The issue with the com port not being recognised above com 9 is a Windows issue,(both XP and Windows 7) but as long as you can keep the com port below 9 its fine. The code writer will fix this when he next updates the program to overcome this . You can change the assigned port numbers under the advance settings for the ports under device manager to get it to work.

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Just an update. The software now has some extra nice touches like stepper motor and fuel pump control,and target idle speed (its a reading, this not a changeable parameter), and more updates are to follow soon. It also runs quite nicely off a CD if you dont want to load software onto your PC. On the hardware side, I have not been able to get the Lucas TTS connector to make up interface leads, so Ive had to make connectors from scratch, which have turned out OK, so if anyone wants a pre programed lead with connector, CD and instructions drop me a line, as Im making a few kits up to order.

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Currently the Rovergauge does not have the full list of features as the ECUmate, the biggest being no display for the lambda trim values, which is being worked on currently. Its also not as easy to use as the ECUmate, if only because you have to have a laptop with you for road tests, which is never that easy in a cramped cockpit but I personally like the mapping table info RoverGauge gives you,(and the fact you can extract it easily) as I think there is potentual to be able to alter the values and program different fuel maps into the 5 available map space in the Eprom (This will require an Eprom programmer to write the new maps back to the Eprom- RoverGauge cant do this).

Cables have costed out ar £35 inc postage, Ill include all the software you need and instructions with it as well.

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The next revision has just been released, with a lambda display showing the amount of fuelling correction going on. Not had a chance to play with it yet.

Edited by blitzracing on Wednesday 23 May 19:57

[blitzracing]

Just a general update.

The latest software now has facility to:

Read all the sensor inputs, engine temp, fuel temp, speed input, RPM, AFM, throttle pot, main voltage, and lambda off sets for both banks to monitor fueling against base map and sensor inputs.
ECU load settings (for auto boxes)
Read and show live fuel mapping data- and specifically what map the car is running, inc the limp home map
Read and reset error codes.
Display programmed idle speed.
Read and POSITION the stepper motor
Pulse the fuel pump or run continuosly for tesing fuel pump relay and pump supply

The scales for the AFM and Throttle pot readings are in percent based on a sensor voltage peak of 5 volts, so the throttle pot and AFM voltages can be checked directly against 100 percent = 5 volts. This can be represented by a correctly set up throttle pot going from 5% to 97% over its whole range. An AFM will show 30-33 % at idle depending on engine size. This reading will change if the idle is higher or lower than its programmed to be-

There is the ability to copy the entire Eprom contents as a .bin file, including the fuel maps.

There is a basic logging facility that will give all the sensor data in a serial text format that could be observered at a later date. This will require some expertise in say Excel to display the data in graphical form. You can alter the scan rate for the sensor data, but as the ECU has a very slow CPU in it, some of the sensor data stops updating as the engine RPM rises, and the CPU is busy doing the fueling, and not updating the serial output.

Ive probibly missed something out......

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The speed readings are purely the way TVR have frigged the ECU speed input signal. The system works by going from no speed input to a fixed speed input at about 3 mph, so Rovergauge is simply telling you the speed generated by the TVR speedo correcting box under the dash.

The Lambda readings are not quite what we thought they would show initially. The data read is held in the battery backed up part of the ECU, and on the surface appears to be a long fuel trim value that the ECU learns, not the short term fuel trim that will be seen cycling as it does with a test meter on the Lambda probes or how its displayed by the ECUmate. I did not think the ECU was smart enough to have 2 levels of fuel trim like modern ECU's do, but this will be some really useful data if we can display both fuel trim levels and this assumption is correct. I did think there was something wrong with my set up as I saw no more tham 3% trim on an Adams Tornado chip, but now I think the basic fuel map is spot on, so very little trim is needed. We have also seen 100% trim added to a car with a Torqueflow AFM. In terms of its reading, if its less than 100% (lower the better) then you will be OK. Dont expect both sides to be the same, as the lambda readings vary between the left and right bank even if you supply both sides with exactly the same amount of fuel- I suspect this is due to the plenum feeding from one side and slightly different air flows.

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Y.H.M