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Gm auto radio swap problems

I have been trying to do something that used to be so simple but in today's world it seems has become an exercise in futility. I own a

2000 Chevrolet express van which has a factory AM/FM radio installed. I would like to replace it with an equivalent AM/FM/cassette unit. I got the first one from the junk yard, installed it and found that the only thing it would do is display 12:00 for about 3 seconds each time power on is attempted. The second one was an AM/FM/cassette/CD radio. It does the same thing and in addition it has a small red blinking led on the front panel which blinks continuously. These radios are reasonably priced at 25.00 and 40.00 which is a far cry from dealer price for a new one. 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? And what about when the battery goes completely dead? They tell me that these radios have to be programmed for the vehicle that they are going into. Is this true or are they just trying to get 85.00 out of me for the programming? If there is in fact a compatibility problem can I reset the radio myself? I'm ready to pull the radio/cassete out of the 1990 I have sitting in the woods, custom install it in my 2000 and do away with all this bullshit. Can anyone please advise me further on this? thanks, Lenny
Reply to
klem kedidelhopper
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Yes, its true.. The dealers are suppose to have tools or know how to do this which allows the radio to work.. You most likely have a CAN network or something like that in your car that is talking to the computer. Most likely a process that isn't in your manual to force the Radio to work with your cars computer..

You'd be better off just putting in a after market..

Reply to
Jamie

Agree with last statement fully. Don't waste time with the GM radio.

But if you must, get a Tech II scan tool (should only cost about $1500 or so) and you can program the system to work in your vehicle. The radio has the VIN of the vehicle programmed into its NVRAM and that must be updated, if the VIN doesn't match the VIN in the vehicle's main computers, no radio...

Reply to
PeterD

So what it amounts to is the radio is a one shot deal. Sure you can pay the cost at the junk yard, (40.00) for the full featured one and then if you don't also pay 85.00 to the dealer to "marry " it to the next vehicle it will live in, yours, it is a worthless paper weight. That's 125.00 for a used OEM radio. I can't help thinking that there is more going on here than simply anti theft. Lenny

Reply to
klem kedidelhopper

Hi!

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

Reply to
William R. Walsh

ed it

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.
Reply to
klem kedidelhopper

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