Prev: Unknown SM 5-pin device.
Next: Valve/tube, A/R fault
From: klem kedidelhopper on 16 Jul 2010 11:49
On Jul 16, 11:16 am, "William R. Walsh" <wm_wa...(a)hotmail.com> wrote:
> Hi!
>
> > The dealer tells me that junk yard radios will not work as they go into
> > theft mode as soon as you remove them from the vehicle. If that is
> > so why didn't my original radio do this when I removed it and reinstalled it
> > numerous times?
>
> The dealer doesn't know what they are talking about, and they are
> mixing things up. Collectively, GM refers to all of these systems as
> TheftLock (except the earliest one, which is called Delco Loc II.) I
> don't know if there was a Delco Loc I or not.
>
> Early Delco Loc and TheftLock radios could or did have a code in place
> that would have to be entered if the radio lost power.
>
> The later radios, such as your 2000 model use a different approach. A
> small EEPROM on the board holds a copy of the VIN (along with other
> parameters) and this is checked over the CAN bus with what is stored
> in another computer. If the two do not match--or if there is no
> response from the CAN bus, as there would not be if you were bench
> testing the radio--the unit will not power up or display anything
> other than the clock.
>
> There are a few solutions:
>
> 1. Install an aftermarket radio.
> 2. Pay the dealership what they want to program the new radio.
> 3. Open the radio up, locate the EEPROM that stores the VIN and
> disconnect it. This will cause the radio to report things such as "CAL
> error" and complain, but it will work normally otherwise. This is
> somewhat difficult because GM house-numbered *everything* in these
> radios, even common parts like the EEPROM.
>
> Some parts have their normal numbers, but many do not. There are some
> equivalency tables on the web that you might find.
>
> On many of these, pushing several of the front buttons at once will
> result in the radio powering up and running despite TheftLock. I
> suspect this is a diagnostic test mode, though the set operates
> normally. However, late model (2006 and later for sure) radios have a
> time-out, after which they will shut off. The one from my 2003 S-10
> played for hours this way, so I don't think it does.
>
> William

I thought about the possibility of removing the eeprom but I would
first have to buy the radio and then start screwing around with a
circuit board that like you said we don't know where this part is and
I would not have a schematic for. I might actually pick on the wrong
smt and then what? It's a long shot at best and seems like expense in
time money and more frustration. I guess that I'll abandon this idea
and just take the one out of my 1990. I know that I can simply apply
12V to it and it will come alive, like things were meant to. Thanks
for all the information. It was a real education. Lenny.
First  |  Prev  | 
Pages: 1 2
Prev: Unknown SM 5-pin device.
Next: Valve/tube, A/R fault