Are Obama's limousines carbureted?

[markci]

I can’t imagine anyone putting in the effort to sabotage the ECU in the limo. The thing is a tank in the shape of a car. The only hazard would be to bystanders.

[Imasquare]

@Mr.Moto

More information is coming in on the demographics of the Toyota acceleration victims, and they skew extremely old. The average age of them appears to be about 60 - way more than the average age of Toyota owners in general.

Sudden acceleration issues in the past have often been caused by older drivers who in a crisis mistake the gas pedal for the brake.

Start here for many explanatory links.

I read something similar a couple of days ago. But why are confused older folk confusing the pedals in Toyotas rather than Nissans or Hondas?

[markci]

@Imasquare

I read something similar a couple of days ago. But why are confused older folk confusing the pedals in Toyotas rather than Nissans or Hondas?

For the same reason they were doing it in Audis in the 80’s, I guess. Nearly destroyed them in the US market but it turned out to be overwhelming, maybe entirely, driver error. Media attention does funny things.

[DanBlather]

Check out thislink. A guy logged into the dealership he used to work at and remotely sabotaged customers’ cars.

[Rick]

@VanLandry

No, I dont have any sites and am unsure if it’s ever happened. The ‘very easy’ statement was stemming from information I know about GM’s onstar program. Figuring that presently an On-Star employee can send signals to a specific automobile to flash the hazards and even disable the car itself. I figure if that’s possible then people who develop the software programs could theoretically download a virus to one of these cars to make it behave erratically. I did not mean ‘very easy’ in that any teenager with knack for computers could hack into the system and wreak havoc.

Just because the onstar module is an input to a node on the LAN that does not mean it has control over the network. Far from it. My keyless entry remote is an input to a node on the LAN, but no one thinks I could reprogram my engine control module with it.

@Magiver

I would expect most car computers are hard coded and couldn’t be altered with a virus even though they have storage space to hold error codes and driving data. The few cars I tinkered with for performance reprogramming required an additional chip.

As has been mentioned, BZZZZT! wrong, but thanks for playing. From 1996 until 2007 I was employed as instructor teaching technicians (among other things) how to download new programs to various control units in the car.

@crazyjoe

No but it does mean it is able to send a signal to cut off the fuel supply or otherwise turn off the car. They can also unlock the doors and track the car’s location, so they have a pretty hefty amount of control over the car’s systems.

All of these things can be done without ever accessing the engine ECU at all. Lights, door locks, tracking is all done by the main computer (called in GMese a Body Control Module) Want to turn off the engine? Kill the power to either the fuel pump or the engine ECU (both controlled by the BCM)

@engineer_comp_geek

I happen to design embedded systems for a living. I don’t however have any knowledge of how GM does their thing though. I do mostly industrial controls. I don’t work in automotive.

That said, from poking around on the net it looks like most (if not all) of the “computers” (or more accurately, embedded controllers) in GM vehicles do talk to each other over sort of a can-bus type of thing called GMLAN. It looks like it is possible to do a firmware update to the ECU over the GMLAN. Presumably, a tech would just connect something to the ODB-II port and tell the thing to flash the ECU.

If (and this is a big if) the onstar communication unit has enough control over the GMLAN then it could theoretically update the firmware in the ECU with whatever malicious code was desired.

I am not real familiar with the GM system, but assuming it is similar to ours to reprogram a module you have to put the entire network into prog mode. To do this the entire car is shut down and rebooted by the computer. Whent he computer boot up they spend 35 ms not responding and listening on the network. If no prog command comes, the car boots up normally. At the same time the computers come online the diagnostic tools broadcasts prog, prog, prog, prog. This puts the entire car into prog mode. Engine does not run, lights are off, cluster is blank. Car appears to be asleep. In fact all the control units are up and listening, but not broadcasting on the network. At this point the diagnostic tool broadcasts the new programming.
When it is all over the diagnostic tool broadcasts a wake up call and the nodes reboot normally.

@Gary_T

There was nothing in automotive computers that was date-dependent, and there’s nothing in automotive computers that’s virus-susceptible. It’s a laughably impossible notion.

Actually the latest generation of cars record fault codes in real time and I can access a print out with the date and time of when various codes were set.

[Rick]

@DanBlather

Check out thislink. A guy logged into the dealership he used to work at and remotely sabotaged customers’ cars.

Not factory equipment.

The Texas Auto Center dealership in Austin installs GPS devices that can prevent cars from starting. The system is used to repossess cars when buyers are overdue on payments, said Jeremy Norton, a controller at the dealership where Ramos-Lopez worked. Car horns can be activated when repo agents go to collect vehicles and believe the owners are hiding them.

These units were designed to disable the car, and honk the horn.

[DanBlather]

@Rick

Not factory equipment. These units were designed to disable the car, and honk the horn.

Sorry, should have made that clear. I just thought it was interesting in light of this thread.

[Tully_Mars]

@Rick

All of these things can be done without ever accessing the engine ECU at all. Lights, door locks, tracking is all done by the main computer (called in GMese a Body Control Module) Want to turn off the engine? Kill the power to either the fuel pump or the engine ECU (both controlled by the BCM)

That’s cool to know. It makes sense, but I didn’t realize they (GM) were using seperate computers.

@Rick

I am not real familiar with the GM system, but assuming it is similar to ours to reprogram a module you have to put the entire network into prog mode.

If safety is a concern, a smart designer would include some safety interlocks to prevent entering prog mode, such as the ignition key in the “Off” position and the throttle sensor position is zero.

If a smart designer is concerned about tampering, a smart designer would computer a hash over his code as it exists in flash ROM and then not allow it to execute on power-up unless the computed hash is correct.

[Rick]

@Tully_Mars

If safety is a concern, a smart designer would include some safety interlocks to prevent entering prog mode, such as the ignition key in the “Off” position and the throttle sensor position is zero.

If a smart designer is concerned about tampering, a smart designer would computer a hash over his code as it exists in flash ROM and then not allow it to execute on power-up unless the computed hash is correct.

Why? Since you can only put the car in prog mode while it is connected to the diagnostic tool, it should be fairly safe to assume that this will not be done while the car is being driven. Kind of like asking for a safety interlock to prevent the oil from being changed if the vehicle speed is greater than zero. Not really an issue that comes up in the real world.
Also what makes the OP think that the President’s limo has onstar to start with? If ever in the history of the world there was a vehicle that did not need onstar the his limo is it.