Thread: ODB II and GM DIC

Originally Posted by cw95403

Anyone know if you can tap into the GM DIC (Driver Information Center)? Is that part of ODB II?

DIC provides users with this and more:

fuel used
MPG/KPG
trip odometers
oil change schedules
HOBBS meter (engine hours)

Thanks...

None of those are standard ODB-II PID (item you can read from the interface) AFAIK. You may be able to get them from a manufacturer specific PID though. Good luck finding info though.

any luck with interpreting the signal for the DIC?

anyone else for that matter?

specific vehicle is a '06 G6 with the DIC in the radio. i know they produce a dash kit that keeps the functionality (simple LCD display), but i'd love to be able to incorporate the data into a self designed program i want to make...

anyone have any ideas? i know there is an aftermarket headunit mounting kit that retains DIC info. what would one do to interpret the signals? (given i can figure out what wires are associated wwith the DIC)

is grabbing those signals and sending to the CPU for interpretations something more for the hacking section?

the chip is on the back of the cluster, Its actualy part of the dash cluster and not directly dependant on the cpu. Depending on the manufacturer I beleve yours has a motorola 68MC9S1 Pins 49 , 7, 23 are your data, rts and rtc yes you would need to hack the dash, I can get you the specs , pinout if you give me the make and model of the car.

I just bought an elmscan5 and i am sniffing the classII data trying to figure out the protocol. This is among the things on my list. I will post my findings.

on my 04 impala, the DIC seems to have a physical address of 61. I made a list of all the modules with heartbeat signals. I then unplugged my DIC and 61 stopped beating.

The DIC is available on some Vehicles and can be updated. I know that you can update it on the Chevy Malibu and the G6. On these two vehicles the entire message is packed within two messages. Because CAN limits data bytes to 8 per messages a DIC with 16 character display requires two messages to fill the DIC. The lettering is stardard ascii and will most likely only be available on the low speed single wire can network NOT the high speed dual wire network. You can simulate this messages by sending the a messages with the appropriate arbitartion ID on CAN. The message however will be over written as soon as the BCM (or whatever module normally sends the DIC messages) sends another message. Fortunately this is not normally a periodic message but rather a event driven messages. This means that when the door opens a message is sent an another one is not send until the door is closed and so on. This is probably one of the easiest message to reverse engineer as it is event driven and filled with ascii databytes that a lot of software can view in that form. There is an online demo of this exact feature at "http://www.intrepidsupport.com/present/hijackdemo/" But the software here is ment for professional engineers and it's price is set as such, so It may not be what you are looking for (or maybe you are an engineer and it is), but they give a good idea of what you need to do to reverse engineer the "Message Center" or DIC.

There is also the non text-based version of the DIC in some cars. I noticed that in my impala, the radio display also uses ascii commands several messages long. Everything shown in that video can just as easily be done with a simple terminal program. It is cool none the less.

Did anyone ever have any luck with tapping into the GM DIC?