Ok, so if you've followed any of my other threads you'll see I'm having an issue with my radio locked and airbag light on (accompanied by B1001 Option Configuration Error and B1390 Device Voltage Reference Input Circuit) in my 00 SSEi.

I went thru the diag as seen in the below thread which led me to "replace the bcm"
2000-2005-other-than-gxp/topic51466.html

If I look at the VIN programmed into the existing DIM it reads "0G00000000000000" which lends credence to the module being troublesome. I tried programming the actual VIN into the old module and get the "Loss of Communication" on the Tech II.

Now I picked up a junkyard DIM (from LeSabre, same exact part number on the module) and when I go in with the Tech II I can read the existing VIN from the LeSabre but when going to program the correct VIN back in I'm getting the same loss of communication error. It flashes storing VIN for a second then goes to the loss of communication screen

I realize this is a pretty specific issue but I'm hoping someone could help lead me in the right direction.. Is the replacement module bad because I'm getting this loss of communication error? It is a clone Tech II but I haven't run into any indication that the tool would be the direct cause.

I would suggest that DIM failures are not very common at all and the chances that you just happened to pick a vehicle at a wrecker with yet another bad DIM is highly improbable.

As for the clone Tech2... That may well be part of the problem. I'm just not sure how you can eliminate it as a possibility without another real Tech2 to confirm. I have a friend with an STS who also has one of these clone scan tools. He has occasionally had problems reading some data from modules that were fully operational. All he would see is a string of nonsensical characters in place of things like a part number or VIN.

I don't believe that the DIM's in these cars have downloadable calibrations (unlike say the ECM). By this I mean that I'm certain the software is already fully programmed into the module during manufacturing. There are several option parameters you need to configure as part of the process to setup a new DIM, but otherwise, as long as the part number is identical you should be fine.

Have there been any aftermarket "enhancements" to the car? I'm almost thinking you may have a wiring problem somewhere.

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Bose Luxury Sound System w/Touch Screen Navigation, Addition of Factory XM, 2005 MY Antenna, OnStar Upgrade (3G),
RainSense Wipers, Backup Camera, '00 Style Door Panel Courtesy Lights, Heated Washer Solvent, 2X Remote Trunk Release,
Turn Signal Mirrors, Center Console Courtesy Lamp, Rear Outboard Heated Seats, PVD Chrome 18" Factory Rims, Upgraded
Carbon Fibre Appearance Interior Trim, Highly Modified Main Body Harness, Instrument Panel, Door, Door Panel & Headliner
Wiring Harnesses, Custom Fuse Box & Tire and Loading Information Decals, Additional Acoustic Insulation

The car is all factory -- it did have some wiring issues when I bought it (brake light spice under the seat corroded and a couple wires had water damage near the drivers front sill (power feed to DDM). Those were taken care of and the vehicle was fine after those fixed. Took care of that last summer.

As for the non-programming, the below link (although for the Uplander) does suggest that when B1390 exists the DIM becomes read only and won't allow any changes. I'd think GM would have similar logic on this vehicle.
http://ww2.justanswer.com/uploads/HE/he ... _b1390.pdf

I'm not ruling out a wiring issue entirely but for what it's worth the vehicle did pass the diagnostic check as outlined in the check:
These are the results of my vehicle as measured:
Main Power to Main Ground: 11.3 V
Main Power to Reference Ground: .7 V
Reference Power to Main Ground: 10.8 V
Reference Power to Reference Ground: .6 V

Can you think of any other circuits that are must check in this harness?

I read through the DTC information for B1390 and it's similar the Uplander with the exception of some terminal and connector references. I would still recommend physically inspecting the affected wiring. Because you can communicate with the DIM, even if it's only to look at the existing VIN, it suggests you can connect and therefore the Class 2 Serial data lines should be intact.

As for power and ground, this would be my starting point since it seems to be at the heart of this DTC.

The DIM is connected to two separate grounds. One is located at the splice pack (small black box bolted to the body) behind the front passenger door sill plate at the base of the 'A' pillar facing rearward. The wire that you're looking for will be 20AWG that is black with a white stripe (for some reason, this is one of very few instances that the manual doesn't specify which cavity the wire will be in). There may be more than one BLK/WHT wire so I'd check all of them for signs of corrosion or other problems. The top cap where the bolt end is located does separate from the body of the splice pack. Taking this off will allow you to check the condition of the bus bar in the cap and the terminals that plug onto it. To be honest, this is not the highest on my list of suspects. The ground does not pass through any other connectors between the DIM and this grounding splice pack.

The second ground connects directly to the battery. If you look under the rear seat on the passenger side, you'll find a small wire that comes off the negative battery terminal. This wire passes through a single cavity connector that will be easily visible and goes into the main body harness. I would start looking here first because these cars are known to have moisture and corrosion problems under the seats and carpeting. Make sure that wire isn't damaged or pinched. Separate the connector and check for any sort of corrosion.

The two positive feeds into the DIM are also not high on the suspect list. Both originate at the fuse block under the rear seat and are contiguous wires traveling straight to the DIM. Like the first ground mentioned above, they pass through no connectors.

Start there, especially with the ground under the rear seat and let me know what you find. Keep in mind that what you find with your meter may still be out of tolerance compared with what the DIM is detecting.

_________________


Bose Luxury Sound System w/Touch Screen Navigation, Addition of Factory XM, 2005 MY Antenna, OnStar Upgrade (3G),
RainSense Wipers, Backup Camera, '00 Style Door Panel Courtesy Lights, Heated Washer Solvent, 2X Remote Trunk Release,
Turn Signal Mirrors, Center Console Courtesy Lamp, Rear Outboard Heated Seats, PVD Chrome 18" Factory Rims, Upgraded
Carbon Fibre Appearance Interior Trim, Highly Modified Main Body Harness, Instrument Panel, Door, Door Panel & Headliner
Wiring Harnesses, Custom Fuse Box & Tire and Loading Information Decals, Additional Acoustic Insulation

Thanks for the info and feedback -- have some bad weather today so I probably won't get another look until next weekend. Will update

Hey dalder,

I have been delayed by a bunch of bad weather and other plans (not relying on this car for transportation yet)

anyways, much thanks on the good advice -- tested connectivity of the ground to the pass A pillar and it was good there. Tested ground back at the connector that leads directly to the negative battery post and this connection was a corroded mess. Took it apart, cleaned everything up and it cleared up the B1390.

After that it was simply using the Tech II to program the new VIN (after clearing B1390 it came out of the read-only mode), syncing the SDM, and programming the specific options. Great advice -- thanks for going out of your way helping

You're welcome! Glad to hear you've got this beat.

_________________


Bose Luxury Sound System w/Touch Screen Navigation, Addition of Factory XM, 2005 MY Antenna, OnStar Upgrade (3G),
RainSense Wipers, Backup Camera, '00 Style Door Panel Courtesy Lights, Heated Washer Solvent, 2X Remote Trunk Release,
Turn Signal Mirrors, Center Console Courtesy Lamp, Rear Outboard Heated Seats, PVD Chrome 18" Factory Rims, Upgraded
Carbon Fibre Appearance Interior Trim, Highly Modified Main Body Harness, Instrument Panel, Door, Door Panel & Headliner
Wiring Harnesses, Custom Fuse Box & Tire and Loading Information Decals, Additional Acoustic Insulation