[thetao]

A friend acquired a 2008 G6 GT convertible last year. He's non-technical and I'm helping him sort through some issues. Just as the subject line says, the keyfob (with a fresh battery) doesn't work at all, and the DIC perpetually reads SVC TIRE MONITOR. I was originally dealing with these issues separately until I realized both systems share the same antenna. I also realized something else was happening when I tried the non-keyfob method for syncing the TPMS sensors to the car. Absolutely no variation of pressing the INFO and ARROW (Enter) buttons on the DIC put it in TIRE LEARN mode. The display doesn't change, nothing flashes, nothing beeps...just nothing. (I'm sure the TPMS batteries are dead by now, too, but that's more trivial to solve.) A friend with a very expensive Autel scanner (but doesn't live nearby) may be able to verify that the RCDLR is dead.

Another thread here includes a GM bulletin on the problem:

Dead Battery - Loss of Keyless Entry and Tire Pressure...

It happens to everyone at some point. I guess this was my turn. I left my keys in the ignition overnight which drained the battery. I gave my 2008 G6 GT a jump which recharged the battery. Unfortunately, the keyless remote/start system doesn't work anymore and my tire pressure system reads 2...

www.g6ownersclub.com

So I think I have it figured out that far. But a couple questions for anybody else who's experienced this?

1) So it's normal for TIRE LEARN to not appear if the antenna is non-functional? I wish the display would flash ERROR! or something helpful instead of making me sit in the car for an hour, thinking I was doing something wrong.

2) Something I read suggests that the fault in the RCDLR is due to a software bug. That is, once the new antenna has new software, this problem shouldn't happen again. But given that it's caused by a dead battery/low voltage, I'm not sure that sounds right. Was this problem ultimately caused by hardware or software?

3) Out of curiosity, will any consumer grade OBD2 readers pull codes from GM RCDLR's? Mine certainly doesn't.

Thanks!

 

[thetao]

Addendum: Would somebody also describe where it's located? If I crawl in the trunk and look up, will I see it? Or do I need to take the seats out, etc.?

 

[thetao]

A short update for any future readers. I got some brief access to the car last weekend. It's not the fuse...which also covers the XM radio. I found the RCDLR antenna. It's in the trunk, mounted to the tail side, and covered by the same large piece of body trim that covers the fuse box. Here's a diagram. The wheel well is to the left.

Unfortunately I didn't have time to figure out how to remove the other various interlocking body panels to get direct access. I could feel it and partially see it, but then had to abort. Will try again in a couple weeks.

 

[thetao]

Another short update. Due to poor weather and tight schedules, I wasn't able to get physical access to the RCDLR box prior to my friend with the fancy Autel. He was able to find the RCDLR module but could not communicate with it whatsoever. Curiously, he was able to put the car in "Tire Learn" mode...at least for the first wheel. He could not get the keyfob to pair with the car. From this it seems either 1) the RCDLR antenna is completely fubared, or 2) one or more of the power, data, etc. lines are out. Really wish I'd been able to get my hands on it first. When I finally do, if all lines appear okay, then I'll be replacing it.