Engine/Transmission (1998.5 - 2002) ECM updates

[slo-ryde]

The ECM is just a small computer running code that's stored in non-volatile memory. When you flash the ECM you rewrite or update the code. It's similiar to flashing the BIOS on a personal computer.



If something goes wrong during the flash you'll probably end up with a brain-dead ECM. The scan tool used to flash the ECM runs on batteries. If the scan tool powers itself off or is running at low voltage (batteries not sufficently charged) communication errors will occur.



The scan tool should be fully charged or plugged into the a/c charger when doing ECM upgrades. I think this is even documented in the procedures. But hey, who reads the stinking manuals!

 

[kaffine krazed]

The scan tool does not have it's own battery. It gets it power from the trucks batteries. To get the DRB to power on without a truck they have a box that hooks up to the port the truck cable plugs into then you hook it up to the MDS by another port so you can update the DRB. You can't have the DRB pluged into the truck and an AC power source at the same time. There are 2 ways to flash the ECM either with the DRB hooked up to the truck and the MDS computer at the same time or by hooking the scan tool up to the MDS and download the update to it then take the DRB and update the truck without the MDS connected most techs that I know of do it with the MDS hooked up because it is faster unless you are doing sevral cars with the same program.

 

[slo-ryde]

Well, every scan tool I've seen for the last 4 or 5 years definitely has batteries. There's a jack on the side that's only used for connecting the a/c charger.



Maybe we're talking about two different animals? The one I'm referring to connects to the OBD port, usually on the driver's side under the dash. It can be used to read out fault codes, block or disable certain codes, and update or flash the ECM.

 

[kaffine krazed]

What scan tool are you using. I'm using the DRB3. I have never seen a way to power it on without it hooked up to either both connectors on the MDS or hooked up to the car.

 

[slo-ryde]

Originally posted by kaffine krazed

What scan tool are you using. I'm using the DRB3. I have never seen a way to power it on without it hooked up to either both connectors on the MDS or hooked up to the car.

I'm referring to the ones used by the dealers. Some of them even have a pc on a cart that connects to the in-house network and allows downloads of tsb's, service manuals, parts catalogs, ecm updates, recall campaigns, etc. . I think it's Toyota that has a small webcam style camera that the techs use to take pictures of stuff to send back to the home office.

 

[kaffine krazed]

The DRB3 is Cryslers scan tool. It gets it's power from the car.

 

[slo-ryde]

I'm taking the truck in tomorrow for service. While I'm there I want them to check for any error codes and ecm updates. I usually try to sneak a peek while they work on my vehicles. If I'm lucky maybe they will let me watch.



Does Nevada require that vehicles be ODB compliant? California certainly does, maybe that's why I see a different kind of scanner?

 

[obert]

Slo ride-- what do you mean by OBD compliant?

On Board Diagnostics simply is a computer that self checks its self.

(that sounded redundant)



Perhaps that all emission related sensors are still "factory"?...

 

[kaffine krazed]

I'm assuming you mean OBD 2. That is a federal mandate since 96. The only scanner I'm really famialer with is the DRB3, I've used GM's Tech 2 a few times but always had it connected to a car so I don't know if it has a battery or not. We are supposed to be getting a new computer system to replace the MDS system and mabey a new scan tool to go with it but I haven't gotten much info on the new setup to know if it's a new scan tool and computer or just a new computer.

 

[slo-ryde]

Yes, OBD II is what I was referring to. I'll be at the dealer in the morning and I'll find out exactly what model they use.



I'm going to ask them to check the ecm version and pull any error codes also. The motor doesn't seem to be running the way I think it should be. It's new with only 1,000 miles on it which could certainly be part of the problem. A lot of people are posting that the cummins motor isn't broken in until 10,000 miles. I figure it's cheap insurance to have them take a quick look at the ecm, better to find out early about any gremlins!

 

[slo-ryde]

My first visit to the local dealer did not go well. They had the truck all day, I had to call them 30 minutes before closing time to find out the truck was "ready", they couldn't find anything wrong with it, and I barely managed to get the truck before they closed.



I'll be back in the morning for round two, maybe the guys in the parts department can be more help.