Radio Locked!

[68vwdubb]

Hello All!

I am currently working on adding the slave cd player to my 90 convert. And now I have the oem cassette radio locked! I have looked through the service manual and had no luck with it. Any info would be Greatly Appreicated!!! I understand that sometimes you have to have a dealership call in to get a code or something, but a friend of mine that works at a GM dealership is unsure of how to pull the code out of the radio.... so that we can call in.


Thanks in advance for any help or ideas.

[KDirk]

Now this is interesting, because I am not aware of any anti-theft feature on the 90/91 factory head unit. The theftlock feature was not implemented on factory head units [so far as I know] until at least 95 or 96 at the earliest. Maybe a few earlier units on high end vehicles like Corvette, but most GM products did not have this until after the adoption of OBD2 (1996) which necessitated the move the GM's class II comm network. Not to ask a stupid question, but are you certain you have the original factory head unit, and not a later GM unit? Does the radio display show something to the effect of "LOCK" or "LOCKED"?

Newer GM vehicles (typically with class II or more recently CAN bus communication networks) have the vehicle VIN stored in the radio configuration memory. When being relocated to another vehicle, a TECH II tool is needed to reprogram the radio for the VIN of the target vehicle. By my understanding, the VIN of the source vehicle is also required to be input to clear the theft lockout feature. This procedure would not be applicable to the Reatta in any case as it lacks the more advanced communication networks of the post-1996 vehicles. In fact, I doubt such a radio could be used in the Reatta as there is no way to re-program it over the ALDL/OBD 1 network used in the Reatta.

KDirk

[68vwdubb]

Thanks for your reply and your help! I can pull the radio back out, but I am very certain that it is the original radio to the car. It displays "loc" when I start the car now. It worked fine prior to being removed for the best part of an hour to make room to figure out how to and where to run the slave cd harness! Always my luck!

[NCReatta]

I agree with Kevin... I'm intimately familiar with the radios in Reattas, and to the best of my knowledge, there is no such anti-theft decide on the factory radio. Are you sure you're dealing with factory stuff?

[juddev]

[NCReatta]

1990/1991 Reatta factory radio:

[Ronnie]

Of The Locked Radio

[68vwdubb]

Doubt me if you want, but this is probably only the 9th Reatta that I own(ed). It certainly looks like an OEM radio to me. I will have pics later today. thanks again for your help. Its got me puzzled as well, but I know what it says. I will post back a little later. thanks

[68vwdubb]

I have now have a couple pics, but when I try to insert the images, it keeps telling me upload failed. Is there something I need to do differently? Thanks

[Ronnie]

The photo is probably too large or is in the wrong format. I don't know what the file size limit is on this forum. On my forum it is 2 megabyte. Valid file extensions are: gif jpeg jpg pdf png

[68vwdubb]

Thanks Ronnie, you are correct. I just noticed that is states that. Hmm, now I will have to try to figure out how to resize it.....

[2seater]

Forgive me if I am way off base but I thought "loc" meant a local station. I am not sure why that would even matter but I have seen that reference somewhere before.

[68vwdubb]

Hello 2Seater,

Thanks for the reply. Well I guess I never thought of that, but the radio no longer has any functions at all. It worked perfectly before removing it and now it won't do anything. ???

[wws944]

Have you tried "rebooting" the radio by pulling fuses 11 and 13 for a moment?

[Ronnie]

Thanks Ronnie, you are correct. I just noticed that is states that. Hmm, now I will have to try to figure out how to resize it.....

Do a Google search for PhotoScape. It a simple photo editor that is capable of resizing photos when you save them. Best of all it's free.

[68vwdubb]

How about this. Take a look. Ever since I put the radio back in after having it out for a little over an hour, this comes up on the screen and I have no functions on the radio. thanks again for your time and help!

[KDirk]

Well, that removes all doubt. Now as to how to reset it. I did some looking around online, seems almost all posted data on resetting GM radio lockouts pertains to newer (late 90's and up) units with "delco-loc" and "theftlock" systems. The former utilized entry of a 4 digit code to reset the radio, the latter is reset by the tech II tool at a dealership as already discussed.

I did find references to 89/90 Pontiac Bonneville and 6000 radios having to be unlocked by pressing and holding the mute button. On the 90/91 Reatta radio, the mute function is unlabeled, but is accessed by pressing the center of the volume rocker inward such that both volume up and down are activated simultaneously. You might try this, and see if holding it for several seconds unlocks it.

Only other thing I found was that pulling the radio fuse with the radio on and then reinserting it, sometimes repeatedly (5-10 times) will eventually clear a LOC condition on GM radios of this era. So, that might be worth a try since it is simple enough to do.

KDirk

[68vwdubb]

Hello KDirk,

Thanks for your info and help! I just went out and tried the mute idea. I tried several times... no luck. So I guess I need to try the fuses next, huh?

[KDirk]

I would try the fuse pulling approach next for lack of another idea (just yet anyway). I will get out my 1991 owner's manual to see if it covers this at all (91 has the same factory radio). The FSM did not make any reference to a security lock feature that I could find in a brief skim over the section on the radio.

As an aside, some newer radios (Delco-loc and Delco-Loc II variants) that use a code number are reset by a procedure in which a serial number is pulled from the radio on the display by a series of key presses. An automated 800 number for dealers is then called with this number, and an unlock code is read back to the caller. Another series of key presses is then used to enter the newly issued code number. This procedure does not apply to the Reatta radio as it requires HR and MIN clock set buttons on the radio (present in mid-90s and later models) to do the code entry. I only mention it here on the chance someone else may offer it as a solution, but it will not work on the 1990/91 Reatta factory radio design.

KDirk

[68vwdubb]

Dumb question, but I assume these are the fuses behind the little panel on the passenger side console?

[KDirk]

Yes, there should be a radio fuse there (the inside of the cover shows the fuse numbers, values and function). Based on what I found elsewhere on-line, the radio should be on (at least showing "Loc" in the display) and then the fuse should be pulled for several seconds. Reinsert the fuse and check radio. If still showing Loc, repeat up to several times, as apparently it sometimes takes repeated interruption of power to clear it.

I did read through the radio section of the 91 owners manual, and did a thorough re-read of section 9/radio and accessories trouble shooting in the service manual. No mention at all of the lockout feature, or how it is cleared, anywhere to be found in either book.

Before I changed the stock radio in my 91, I had disconnected power to the car any number of times while doing repairs, and never once had the radio lock activate. I cannot figure out what caused this to happen to yours. I did just happen to think that you should disconnect the CD harness from the radio, perhaps there is a problem there. Keep in mind that the CD and radio communicate via the E&C bus (dark green wires in the radio-cd interconnect harness) and perhaps there is a pinched or damaged wire shorting the bus to ground or voltage that may have triggered this.

If the problem goes away when the CD harness is disconnected from the radio, this tells you either the harness or the CD player is bad. Then test this theory buy disconnecting the harness on the CD player end, and reconnect it at the radio end. If the problem recurs, it is the harness. If it does not, it is the CD deck. Simple process of elimination.

KDirk

[Ronnie]

It appears you have a '91 radio.

To unlock your radio read this:
Loc message on stereo

and then read this completely:
GUARANTEED DELCO GM RADIO THEFTLOCK UNLOCK CODES get it fast or it's free | eBay

[68vwdubb]

Thanks guys for all the info! I really appreciate all your help. I went and read all the instructions on the ebay listing to obtain the 4 or 6 digit code, with no luck. The "loc" screeen never changes.

BTW, Ronnie how did you determine the radio is a 1991?

thanks again

[KDirk]

Ok,

The ebay link Ronnie provided is for Delco radios that are newer than that used in the Reatta. Please look at my post #19 above, this is why I wrote the whole second paragraph in that post to try and prevent confusion. There are at least three main variants of Delco radios with various theft lockout schemes, the 90/91 Reatta radio is not one that can be cleared by the procedure being offered in the ebay link. The other older forum thread linked also references this type of radio, but again does not apply to the Reatta stock head unit from 90 and 91. Note the lack of "HR" and "MIN" buttons on the Reatta radio, that are clearly needed in the procedure on the ebay link.

The 90 and 91 Reatta stock radios are visually identical, so the only way to tell any difference is to look at the model # and production date tag on the radio enclosure. I am not aware of any functional difference in radios for these two years, though there may have been subtle running changes for internal parts changes or improvement. And again, the FSM makes no reference at all in the troubleshooting charts to the "Loc" condition or how it is cleared. Thus, something strange is going on.

Did you already try pulling the fuse, and isolating the radio from the cd player and it's harness? I'd at least like to know that these were tried and ruled out. If so, then further research is going to be needed on what caused this and how it is cleared.
I hope this isn't coming off as a bit terse, as that is not the intent. I'm just trying to get to the bottom of this problem.

KDirk

[Ronnie]

After reading the first link I sent you I thought it would reasonable assume this only happens to '91 models. And since I don't remember hearing '90 owners say they have experienced this problem I figured it must be a '91 radio. Short story is it was just a guess. Do you have reason to think this I'm correct?