Re: my earlier post in the electric supercharger thread:

https://www.crossfireforum.org/forum...&postcount=107

I have been trying to scan the OBD port on the Crossfire without success. I believe the vehicle used the ISO protocol but so far I haven't managed to get this confirmed for sure. The only protocol I haven't tried yet is CAN but I think it is unlikely this is being used due to the age of the Crossfire's SLK platform - I know it uses CAN for comms between the various control systems in the car, but that doesn't mean it is used for the OBD. Also Racelogic produce some nifty CAN attitude/yaw monitoring stuff but their website suggests that CAN is not available through the OBD port on this car, but again this may only refer to the CAN bus between the specific ESP/ABS modules that they are tapping into.

I have searched about the forum and Service manual but can't find any references to anything other than the DRBlll.

Has anyone used anything other than the DC's DRBlll to scan this car and if so what tool/protocol did you use?

Anyway, I am waiting for some parts to arrive to build up a multi-protocol reader which will support CAN and then I'll have another go.


Simon.

 

Simon: I have spoken with MOTEC about a computer for the car but they seem completely disinterested unless I throw a ton of money at them... As you probably know the DRBIII scan tool is manufactured by Miller Special Tools. I am not sure if this is exclusive to the new DC products or is a crossover to the MB... It would be helpful to have laptop access and adjustments to the parameters of the ECU/FMU etc.

If you send me a PM, I can give you the direct e-mail to some of the Crossfire engineers at DC... If you tell them you are working on a SCCA club racer and need the information, they probably will be of assistance... Although they might need to get the correct info from MB...

 

Yeah, I have done some digging about on the DRBlll but without buying one there seems to be little detailed information on which protocols are used for each vehicle, just which modules are required etc. There also seems to be little info on the MB sites. Hopefully the CAN reader will work and we can go from there.

Even once the OBD port can be interrogated it may still not be possible to actually change settings but I guess you have to start somewhere!

I'll PM you regarding the contact details.

Thanks,
Simon.

 

This may help... http://www.autoxray.com/dnload/ScanToolReport.pdf

 

Thanks, I thought for a minute that might have been the answer I was looking for - Page 22 gives the spec for Chrysler DRBIII but just shows the vehicles not the protocols - I like the prices too!

Simon.

 

I have finally made some progress with this. After waiting for CAN chips to arrive then spending hours building a CAN interface I still couldn't 'talk' to the OBD port! But I have now got something working using the ISO protocol! So I can now confidently confirm that the Crossfire does not use CAN for the OBD port, it is ISO.

I am still determining which OBD PIDs the car supports but so far I have been able to read the coolant temp, RPM and throttle position in real-time. I really need to sort some better software now to do much else.

More later...

Simon.

 

Simon: Looks like you're making some progress. I'm sure it's a pain in the neck, but you'll be the first to have a working system.

 

As you know yourself this is the sort of stuff you end up going through with this car; if it wasn't for the fact I actually have a Crossfire I'd begin to wonder if they actually exist, such is the dearth of available info. Still, you forget about all the hassle once things start to work.

I am going to work on this at the weekend, in between the 'fixes' of paint and resin fumes whilst finishing my brake ducts.

 

I still may be able to get the info you need from DC... Let me know if you run into a brick wall and I'll send off an e-mail to Andre'.

PS: I would love to see photos of your brake ducts when completed.

 

A local parts store to me (Autozone - US only chain?) simply used their off the shelf code scanner to read the DTC codes from my car, the only weird thing was that the engine actually had to be running to read the codes. Where as in my old cars, the ignition only had to be switched to the on or accessory position.


You might want to check out http://www.vitalengineering.co.uk

 

Oh, and because the guy acted like he'd never even seen a crossfire before, I highly doubt he grabbed any "special" scan tool.

 

Thanks for that Jpristel, I know there are loads of scan tools around but nobody would tell me which one I needed for the Crossfire, just that 'it might work, we haven't tested it', and was reluctant to spend money until I knew it would work, and all the pro tools are stupid money. I was interested to find out what the protocol was for tuning purposes rather than just reading the fault codes. Also most of all the DIY/low cost OBD readers are based on the Elm chipset that I had already got to hand and had tried. Many of the vendors merely box these up and charge double for them! Looking at the spec the Vital nit seems to be ELM based but with a Bluetooth module added.

Anyway I now know that the Crossfire is ISO so I can start playing...

edit:
When I finally got it to work I didn't have to have the engine running, just the ignition on, at least for the PIDs I was reading at the time.

Cheers,
Simon.

 

I don't think it would have been anything special either, just a multi-protocol scanner. What threw me was that the slk is ISO, so i tried my ISO scantool board but it didn't work. Then CAN was mentioned, so I pursued this, incorrectly as it turned out. I then used a chip that supports more of the ISO protocols and it worked - oh well, you live and learn.

 

Yeah, I've noticed that almost all the scanners are based on the elm 327 chip. However the device from Vital Engineering appears to be the cheapest all around OBD dongles I've found yet. Have you had luck using the elm chips on other automobiles?

 

Yeah, the 323 (VPW) worked on the PT Cruiser and the 322 (ISO) worked on,a Citroen Xara and a Peugeot 307. The 327 (multi) works on the Xfire if you select the fast init ISO protocol (No. 5 I think it was).

Edit: Just thought I better add that although I got the 327 to communicate with the car it was with a terminal emulator only. I couldn't connect to the car using the free Scantool.net software - I always got an initialization error irrespective of whether the engine was running or not.

Simon.

 

An excellent universal scan tool can be found at: http://www.obd-2.com

Get either the tricom or the trican and you'll be good to go on pretty much ANY car.

 

Good info Scott, but the key phrase in their product information is that "Does not modify performance". I think Simon and I are looking for software that will allow us to modify air/fuel ratios for our track performance.

 

entire maps, or just the Mercedes "fuel quality" settings? what is it about the AFR that you want to change/what are you experiencing on the track that merits a change?

 

The car has been retrofitted with dual 3" CAI's, cats have been removed (O2 sensors in place) I run a mixture of 91 pump gas with a % of Toluene and Xylene and a % of Klotz Coxoc. The chip was flashed with a PowerChip Gold 93.

The car seems to be running very lean with a sporadic misfire at idle. Plugs are changed after 3 events.

So, you can see why I need mapping and alteration capabilities.

 

Thanks Scott for the heads up on the scan tools. But like HDDP says my main reason for looking at all this was to enable the modification of the fuelling/ignition maps following any engine mod that may require it. My initial investigations with the Elm chips, which I now have working but are read only, was to establish the protocols that the car uses. The first step will be to log OBD data whilst on the road/track such as AF, ignition advance and other useful data such as actual trottle butterfly position relative to throttle pedal position. This will give a better understanding of what the car is actually doing as opposed to what we think it is doing.

Having established what protocol is being used the aim would then be to write some software to write stuff back to the various ECU's - this is fraught with potential problems I know, but nothing ventured...

Without going over old ground concerning the gains of 'chipping' a stock N/A engine, I don't see much potential for altering maps for the stock car. But for any mods that increase airflow beyond the point that the stock ECU is able to compensate for, you are going to need to look at remapping.

I know there are commercial systems available for this, your company has undoubtedly invested in such a system, but it cost about the same as my Crossfire is worth!

Cheers,
Simon.