bootloader error will not reflash

[toolie]

Need help? reflashing LB7

This happened to me before. Only last time it erased ecm and was unable to reflash. I keeped trying.....and eventually it reflashed.

This time I'm only running a TEST REFLASH and it's failing every time. It will erase ecm but will not reflash new prog. OS is the same. I've switched between the 2 prog many times, it's only a tire size change...the rest of the prog is the same.

Kind of new to this so please keep it simple

Details; none of these combos worked

LB7
Tune V7.5 and V7.4
Alt Keys on/off
High Speed on/off
Battery was <12.5 charged to over >13v
switch USB cable side

[Tordne]

Firstly please make sure you have the latest 7.5.6 Build 116 software installed. You can download from here (http://www.efilive.com/index.php?opt...=48&Itemid=133).

Often people need to pull the radio of info fuses, so that would be worth a try.

Are you able to scan/datalog the vehicle with the Scan Tool?

Cheers,

[toolie]

Tordne

I just updated V7.5 back in February so I think it should be the latest.

I have no problem using the Scan Tool.

I'll try pulling the radio fuse this weekend and try again.

Thanks
Bill

[Tordne]

There was actually an update just last week. Your version should be 7.5.6 Build 116. If you have a FlashScan V2 you should also install the 8.1.2 Build 97 software and update the firmware to 2.06.35.

[toolie]

Tordne

I have the old FlashScan V1 system.

I'll try the V7.5 update later this week.

My latest attempt at running the test was successful. however when I tried the reflash.....
08:30:21.240: Erasing ECM flash memory... (please wait up to 120 seconds)
08:30:21.260: Battery voltage too high or too low.
08:30:21.560: Battery voltage too high or too low.
08:30:21.560: ECM is in an unknown state.
.....again battery reads about 12.8v and I have the laptop conected to a seperate outlet. Not the truck battery.

[toolie]

Update;

As you can see above the battery voltage IS low. To confirm, I ran the the scan tool with the truck running and it only reads 2.4v ????

How can that be, the trucks voltmeter reads +14v and the batteries checked with a multimeter while running read +14v also.......WTF

I don't know if this could cause any issues but I do have a ComputStar Pro remote starter installed.

[2001-GMC-LB7]

If the remote starter is connected to the Can network, unplug it. I have a remote starter on my truck and the key code sensor unit interferes with the scanner and must be disconnected on my truck... Also check the scanner connector for any corrosion or bent pins...

[GMPX]

toolie, don't be offended by this, but we have seen that error before when people don't have the ignition key all the way to the on position when flashing.

[toolie]

Thanks Everyone

It was the remote starter/alarm, I pulled the 3 fuse from that system and no problem reflashing.

Cheers

[GMPX]

Thanks, another one to add to the list, iPod adaptors, XM radio adaptors and now after market remote starters.