Diagnostic scanner for 99 Arnage

The decision to revert to OBD1 for a while was forced on the Arnage because of the change from the Bosch ECU on the 4.4 to the Zytek5 on the 6.75. They got away with it because the international standard for OBD11 only covered cars not heavy motorcars. The Vin for any Arnage that has 32 or 33 for the first numbers following the letters indicates an OBD1 car. OBD1 and 11 are identical sockets but OBD11 covers considerably more sensors but down the same OBD lines. Later CAN cars are a different issue. All scanners must report the pin 7 data but there is more of it in an OBD11 compliant ECU. So when an OBD11 scanner result seems not to access some data on an OBD1 car it is because the data is not there, not because it cannot access it. The factory use of other pins for their own scanners is indicated in the list.

I think that there's a mix up in information here. OBD2 is a standard that was adopted by all manufacturers for cars intended for the US market in 1996. All of these cars have an OBD2 diagnostic port that will provide information such as emission level DTC's. As it was not required for cars outside the US, many manufacturers left them out until 2001 when Europe adopted a similar standard (EOBD). Many cars that had an OBD2 socket also had a proprietary diagnostic socket that would allow them to access other non emissions related systems.

Many people call these proprietary connectors OBD1, This is not really a standard, but more of a requirement originating from California for cars to have onboard diagnostics. Different manufacturers adopted different standards and there was a rarely a generic tool that would cover them all. Some cars like Jaguar did not require a tool as there was a way to display trouble codes on the same LCD screen that they used for the clock.

The RR and Bentley SZ model cars from 1992 onwards had a round diagnostic connector to access codes and live data. In 1996, they added an OBD2 connector next to the round plug for cars bound for the USA. The information from that port was limited to emissions related codes and live data (like 02 sensor readings).

In 1999 when they introduced the Arnage and Sereph, they did away with the round diagnostic socket and used the OBD2 diagnostic socket as its only diagnostic socket. As OBD2 only uses 7 of the 16 pins for emissions related codes. They could still use the remaining pins for their other systems. To access all of the systems, you will need a proprietary Bentley scan tool and cable which is programmed to access those systems.

From my experience (and I beat this thing to death trying to figure out transmission and alarm issues on the Brooklands and the Arnage), unless you have the OMITEC scan tool, you cannot access all of the systems (climate control, alarm, suspension....). That's because they're not a CAN bus. I was able to access many of the engine systems on the Arnage using my Autel scan tool and read the live data through the generic OBD2 menu option. The autel does havea specific Bentley Arnange menu but only for models 2006 and later. I assume that the car had a major update at that time and adopted CAN which was a standard that was going to be required for all models after 2008.

In any case, the SZ cars with Zytec supported OBD2 in a limited fashion like many cars did from 1996, so if they reverted back to the very same ECU's used on the SZ cars, it would have supported OBD2 in the way that I described.

There is something very suspicious about my car (SCBLC31E91CX05818)'s response to having anything plugged into the OBD port. Have you all been suggesting that Bentley OBD11 doesnt play nice with normal protocols? In particular I cant get any BT signal to come out of the Arnage socket. I have two adapters so the problem is unlikely to be the adapter as neither can be easily connected to by my phone's BT scan function? One of them IS seen in a BT scan and the phone wont then pair to it. The other one isnt even seen, though all appropriate lights DO go on when i plug it in! the manufacturer says both need firmware upgrades but that isnt why the adapters arent putting out a BT signal.

What is really unusual is that my mechanic had no trouble plugging his Autel into the OBD11 socket and said so. he unplugged my adapter and plugged it back in again and when He reported no trouble, and he said my adapter was working as well. Blow me down but it was!! It didnt seem to connect to the ECU but it did connect to my phone for a while.

But as soon as I drove home, it stopped sending out any BT signal which is seen by my phone! And now, of course, I cant get it to reconnect!

Has anyone seen such problems before with the Arnage OBD socket?

For any of those still looking for a scanner that has some more functionality on the Arnage than basic Engine ECU information and DTCs:

BIMCOM by SECONS is able to read and clear faults from the Airbag module on my 2000 Red Label (the software confirms this is on PIN 3 of the OBD connector).
The supported ECUs are listed here: BIMCOM Supported Control Units

I've not had a chance to check out any of the other modules yet, but can confirm that it's able to access at least the Siemens SRS module.
The Engine ECU it lists appears to only apply to the later R, RL and T models, but I believe the others units are all common throughout the early models.

It's not a cheap bit of kit, set me back £560 from Gendan Automotive, but might come in handy down the line to dismiss insignificant and erroneous fault codes.

I mostly agree with Alabbasi but to clarify my post, all Arnages and Seraphs have the sixteen pin OBD11 type socket. I am using OBD11 as a shorthand since the OBD1 systems have the same socket (not the round one.) The pre 2000 4.4 Arnages etc had Bosch ECUs and were OBD11 The 6.75 engined ones 2000- 2003 have the Zytek5 ECU not the earlier SZ Zytek3 (round socket) and were OBD1.
Post 2003 the VW based diagnostic software was adopted and the Arnages were OBD11. 2006 the Canbus system became standard. Although there is a Canbus link on the earlier engine/gearbox it did not output to the normal diagnostic. The Seraph has always used the Bosch ECU. Most people are happy with the slightly innacurate shorthand, that OBD11 reports from more sensors than OBD1.
Typically a used Bosch ECU is a few hundred whereas a used Zytek5 can be a few thousand.