I have had a chance to experiment with this critter...actually got it through Walmart.com for under $100 delivered...and I;m very happy with it.


I ran into the "issue" of not communicating when using the manual scan that some folks in the other groups have run into, mainly with the earlier versions of models. In our case, it is the pre-2004.5 cars.


The unit has two different operating kernels. There is an OBDII system upon which is overlaid Jag/LR specific systems that read modules other than the ECM (it reads the transmission, chassis codes, climate control, ABS, etc.) and it reads the engine codes cleanly in automatic, but gets confused on the ECM in manual.


That is because the ECM is our pre-lift cars is NOT fully OBDII compliant! If you have an earlier LR , or one of our 2001-2004 X-types, go out to iCarsoft, and update your unit to the NONOBD kernel. It will read back into the early 90s, and it will work in manual mode.


What you lose is the ability to read all OBDII compliant cars, When you use the OBDII kernel, it auto-detects the ECM protocol, decides that the Jag is a Ford 9141, and instead of using the Jag-specific codes it uses the generic OBDII codes. The NONOBD uses the Jag specific codes that apply up to the point where the models went fully compliant.


By the way...it reads every code, including the historicals, back to the day the computer was initialized. I found that all of the modules and the dash in my car were replaced in 2005...talked to the PO, and found that my car was on a bridge out in the midwest during a thunderstorm then, and received a secondary lighting hit that fried the electronics.


He still had the work orders that showed that all of the computers, the entire under-dash and under-hood harnesses, the fuel pump, and just about all of the sensors on the car being replaced and reprogrammed by the dealer. Cost was about what the car was worth...


Anyway, back to the i930...the 'small' version can only contain a single system, so its either one or the other...the new model with the larger case and display is supposed to hold both systems...but at the price, it is still a great item to have!

 

Actually they ARE compliant but the 930 just hasn't quite got the right software yet.

Still, a handy work-around.

 

I find that the locations and codes are compliant, but the bus timing is a bit unusual. At the 2004 facelift point, they made the timing fully compliant.

I had the same issue with my Ultraguage on the Disco II; almost compliant with the Ford 9141, but just different enough that I couldn't use the same settings in, say my Ford Explorer. The UG has both protocols and can sense the difference, the 930, as you say, can't with the '05 up kernel. I understand that the new i930ii can, but I haven't seen one yet.

Scanned a friend's 97 Disco I with it today, correctly identified his 3 Amigos issue and cleared the codes after the sensor change.

Still, for 65 quid, I'm happy with it!

 

Which of the bus timings?

Everything I've tried "just works" so seeing the reports on the i930 is odd.

 

The actual bus timings are different; the 2002 is sending at about 41 kilobaud, most cars in that timeframe send at a bit over 10.5 kilobaud, the 2005+ send CANBUS at 250 kilobaud, and 2008+ use CANBUS at 500kilobaud.

The timing in the i930 interface is software-generated and uses a bunch of code, so it can't select between the two. The OBDii code is installed by default, to make the reader more or less universal. It uses a universal library, but that is weak on the earlier JLR codes.

The non-obd is set up to read the oddball 41.6 speed accurately, and it has the JLR specific DTC library...and it cost them a pretty penny! The early JLR protocol was quite advanced for its time, and much of the code was absorbed into the turn of the 21st century Ford protocol...and ultimately into the existing universal codes.

If you have a break-out box and a 'scope, you can actually watch the communications stream and measure the timing. The ELM interface actually just modulates and sends the stream over bluetooth, and uses software to decopher the stream...which is why so many ELM boxes get confused by the earlier protocols...the timings are off a bit!

By way of explanation...Master's in Communications Tech, BS in both Electronics and Electricity, minor in OO Programming (and a Management degree).

 

You look to be confusing two different protocols: ISO 9141 and (Ford) PWM/SCP. The former is the 10.4k and the latter 41.6k.

You're not suggesting these are both on pin 7 are you? So what exactly are you saying is going on? From what I see the Jag is spot on but the i930 is not.

 

That is it in a nutshell, the Jag is on, the scanner is not. They are reading both streams at the same time, and the scanner can't seem to separate them when they hit, the code simply isn't fast enough.

The IDS/SDD gets around this by using two separate discriminators in the physical interface, one for the ISP hex stream, and another for the pulse width mod signals. The 930 simply isn't that sophisticated. Also, the 930 is essentially one-way; it can send a clear signal for erasing codes, but can't otherwise reprogram the PROMs.

The JLR signal (they actually use two pins) is the busiest interface I've ever seen, short of the newer optical buses (and guess who designed those?)

 

Well, they're only low speed (optical may not be, what speed are JLR using?). Even CAN is slow.

 

I'm looking into a new scanner to use on my 02. There is a wide range of scanners, options, and prices. I really want one that works well over cheap, especially with my 02 OBD. Suggestions???