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Need help, won't turn over.

G-862921

Well here's an update. IT STARTED!!!! Turned out to be the lock cylinder but it's a JOB to change it. Need a factory manual and this video is a SUPER supplement. The only thing that differs from the video with my Roadmaster was that the Pass KEY circuit of two wires had a separate two pin connector. This could not pass through the steering column ( might get damaged, so I cut off the connector leaving enough wire and soldered the connector back where all the wires came together. Here s the video:


I could have saved my self a ton of time and effort if I had just noticed that when the pass key circuit is flashing, it means that the car is NOT going to start. Sometimes you just don't notice things as long as everything is kosher.

This is a tedious job and the wires are teeny. There are other hurdles and if you have questions after watching video, just ask.


On making a new key: I ordered a cylinder lock from Amazon for around 40 bucks. It comes with a CUT blank key, meaning no pellet. I took it to a locksmith with two keys that I was using when the cylinder failed. Hence they had the pellet. He read them in a flash and said they were a #4. of 15. (the value is in a bypass method on this thread). He had blank #4 keys with the pellet and using the blank as a cutting guide, cut me a new pelletized key.. Too 32 bucks and 5 minutes.

Honestly, If I had another problem I'd use the bypass method, but it required finding resistors, matching them to the correct resistance and when I was not 100 percent that PASS key was even the problem at the time, I changed the lock. Might order some resistors and have a bypass circuit handy for the future.

Anyway. Got a new starter, ignition switch and cylinder lock so I should be good to go in starting department.
 

BigBoyDale

Member
42
1
8
Buick Ownership
1995 Buick Roadmaster Estate Wagon
Well I wrote a reply in this editor and hit publish and it went poof. So here goes again, doing copy and paste from Word.
I initially changed the starter and then the ignition switch. The ignition switch is quite a chore and you have to drop the wheel and work on down the column. Not only do you have to remove the switch, but there’s a solenoid and dimmer switch mounted to it, so you better have a great memory or a factory service manual with diagram. These aren’t great, but better than my memory.

Installed switch, attempted to crank and nada.

Should have read more about how the pass key works, but didn’t and all of a sudden I’m noticing that PASS KEY is flashing on “bulb test” just before START.
Pulled out manual and found out that when this occurs, cylinder lock is probably bad.

Order lock on Amazon..so here’s how the programming part works:

You get the lock and a BLANK KEY. This key just looks like a door key with no resistor pellet. Hence, you need to find a good locksmith that does automotive keys. I took them, 2 of my old keys that worked when the cylinder lock failed and the blank key. I took the lock, but it wasn’t really necessary.
I told they key tech that I wasn’t getting a reading across the pellet, but he read it and said it was a #4. There are 15 possibilities. He came back and said he had plenty of #4s. There for he took the #4 key with the pellet ( like my originals), and used the blank in order to duplicate the new “cut” on the pellet key. Took 5 minutes. 32 bucks. I used Eastway Lock and Key in Charlotte NC. You could probably mail them your keys if you can’t find anyone.

Anyway started right up after the lock installation. This is a video on installing the lock. It’s tough, but not impossible. If you have questions, just ask.
Video is from BWD and it’s excellent.

 

HotZ28

Full Member
7,062
326
83
Buick Ownership
1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
Should have read more about how the pass key works, but didn’t and all of a sudden I’m noticing that PASS KEY is flashing on “bulb test” just before START.
Pulled out manual and found out that when this occurs, cylinder lock is probably bad.
Glad to here you got it fixed! All you had to to do, was to install a bypass resistor in the two wires going to the TDM, I am sorry to here you had to go through all that expense and hard work!
 

BigBoyDale

Member
42
1
8
Buick Ownership
1995 Buick Roadmaster Estate Wagon
Well I find several fallacies with your statement.

1. The car is not running and I have to find and match a bunch of resistors. These resistors probably have a 5 to 10 percent tolerance. This isn't 1980, so you're just not going to find resistors in every store. No Radio Shack. Probably on Ebay. Then you have to match them up and hack into the circuit and hope it starts.

2. Next, what if the contacts start working again in the cylinder lock and now you have the original key resistor PLUS the resistor you installed in the hack in series with each other. It starts sometimes, and sometimes it won't.

3. Next, the cylinder lock mechanically is old and I have had several in my life that lock up, won't turn, are get so loose you can pull the key out. This can cause other problems, so I had much rather have NEW.

Starting is important and if it lets you down, you're probably out a tow fee which will more than eat up that money and time you saved.

With fuel pumps and parts used in START circuits don't go cheap. Sometimes the cheap comes out expensive.

I'm not a hope and believe and pray person. Stuff fails, especially at the worst time.
______________________________
 

HotZ28

Full Member
7,062
326
83
Buick Ownership
1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
"2. Next, what if the contacts start working again in the cylinder lock and now you have the original key resistor PLUS the resistor you installed in the hack in series with each other. It starts sometimes, and sometimes it won't."
If you bypass the resistor from the steering column

Glad to here that you did a lot of preventive maintenance in the steering column to get the problem resolved, if that was your concern. If you bypass the resistor from the key sender, it can never comunicate with the TDM again! You should have spent the time to read every sentence and understand the instruction in the link. I have only had ONE key cylinder fail in the last 40-yrs, but you may not be that lucky!
 
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BigBoyDale

Member
42
1
8
Buick Ownership
1995 Buick Roadmaster Estate Wagon
Have you ever even done this or are you just depending the the "Billy Bob" hack will work 100 percent of the time forever since he says so on some youtube video. Even he says that he's unqualified to make claims in it's validity.

That's right...YOU'VE NEVER EVEN DONE IT...like the know it all arm chair quarterback.

Well it might have been some work and I don't mind work, but I mimicked the ASE certified tech in the video and can say I actually did it from start to finish instead of never even turning a screw or soldering a wire on this project.

I thought that I gave the most professional method to do this unless you're unloading the car in the near future. Maybe someday (which I highly doubt) when you perform surgery on yours, you will grace us with in's and out's of reality as opposed to your theories.

I consider this thread closed as far as I'm concerned.
 

HotZ28

Full Member
7,062
326
83
Buick Ownership
1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
'I consider this thread closed as far as I'm concerned.'
Sorry, but you do not have any authority to close a thread here! You seem to have been stressed out, during the above comments? I am ASE & EPA609 certified Technician & have bypassed many TDM modules & have never had a problem with starting for years! BTW, I am not like "the know it all arm chair quarterback"!

"That's right...YOU'VE NEVER EVEN DONE IT...like the know it all arm chair quarterback."
You need to go somewhere else to make these comments! You ask for help here, then attack the responded. Sorry, but hopefully you will not get much help here in the future, with any other problems you will have!!
 
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94masterroader

New member
3
0
1
Buick Ownership
Roadmaster wagon
Before this post is closed there could be another issue besides the resistor. The resistor and key may be fine. However, if the body control module is bad, the ECM will not get the pulse it is looking for at pin A25 (fuel enable). Also, the relay to turn on the starter (under the dash) will not turn on. I see all the videos claiming it is the resistor on the key. Maybe in some cases but definitely not all. The signal to pin A25 is a square wave. It pulses a ground signal to the pin which I believe is high (+5v) otherwise. The frequency should be either 30hz or 50hz. It depends on the car and year. I was not really able to verify what it should be. My signal was not there. I checked my resistance. It was fine. I by-passed the relay coil. After doing that the starter would engage. The engine would crank and try to start. I checked the signal at pin A25. Nothing. I built a small circuit to produce 50hz with a 50% duty cycle. I connected the circuit. The ECM just grounds the pulse out. At this point I am not sure if my ECM is bad also. I used the Factory service manual to determine the body control module (VATS) is bad. How can I test my ECM or am I able to use a junk yard ECM to at least get my car started? I know it will not run correctly with a junkyard ECM, but will it start?
______________________________
 

94masterroader

New member
3
0
1
Buick Ownership
Roadmaster wagon
Before this post is closed there could be another issue besides the resistor. The resistor and key may be fine. However, if the body control module is bad, the ECM will not get the pulse it is looking for at pin A25 (fuel enable). Also, the relay to turn on the starter (under the dash) will not turn on. I see all the videos claiming it is the resistor on the key. Maybe in some cases but definitely not all. The signal to pin A25 is a square wave. It pulses a ground signal to the pin which I believe is high (+5v) otherwise. The frequency should be either 30hz or 50hz. It depends on the car and year. I was not really able to verify what it should be. My signal was not there. I checked my resistance. It was fine. I by-passed the relay coil. After doing that the starter would engage. The engine would crank and try to start. I checked the signal at pin A25. Nothing. I built a small circuit to produce 50hz with a 50% duty cycle. I connected the circuit. The ECM just grounds the pulse out. At this point I am not sure if my ECM is bad also. I used the Factory service manual to determine the body control module (VATS) is bad. How can I test my ECM or am I able to use a junk yard ECM to at least get my car started? I know it will not run correctly with a junkyard ECM, but will it start?
 
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