No start no crank help request on 2000 ('00) Buick Regal LS

[jason.arthur.taylor]

This car does not crank.  Make model info:  2000 ('00) Buick Regal LS with OEM 3.8L (3800) gm engine (not super charged) automatic.

 

I have limited knowledge of the vehicle history.  There are no engine codes, but the car has not cranked since I changed the battery.  The voltage while the key is in the "crank" position rises slightly.  To me, this rules out a weak battery or locked engine.  Here is a video of it not cranking: http://jasontaylor.us/20160612_174120.mp4

 

I do not have the proper tools to raise my car at the moment to check the voltage to the starter motor while cranking.  A google search of the part # indicates that the bcm is probably from a buick century, a close cousin.  No idea why.  Does anyone have any ideas?

 

Question: does this dash light pattern while attempting to crank (but not cranking), and acc power pattern (like power windows stopping while attempting to crank) rule out a vats or bcm problem?  This gm model year uses a PASS-Key II (or passkeyII or passkey2) vats model with I think 15 resistor values possible.  One youtube video of a different vehicle (not a w body) suggests a vats problem would stop fuel only, and the car would crank and start for a few seconds.  This one does not even crank.

 

Is it possible that the drive/gear position sensor is broken, and the car is not cranking due to it thinking it is in gear?  

 

Do I really need bite the bullet and purchase the equipment to safely raise up the front of the car and measure the starter voltage while another person attempts to crank?

 

Many thanks in advance for your thoughts and potential help.

EDIT: the solution was to replace the bcm, which was bad because no security light was on and the fuel enable was not on.  (Good scanner software showed in realtime a start request signal getting to the computer, so the only thing that it could have been was the bcm.)  But, deleting vats would have worked.  The resistor banks sold on ebay are dumb since you can relearn to a key with less work in 35 minutes.

[rich_e777]

IIRC if you back the car down an inclined driveway you should have enough room to get a test light clamp on the starter terminal to see if it has power when cranking. Also enough room to pop it a few times with a hammer to see if the solenoid is jammed if you do have power at the ignition terminal on the starter.

 

If you have no power at the small terminal when cranking you may have a bad ignition switch or a Vats issue, try leaving the key in the on position for about 10 minutes then without turning it to the off position or removing key see if it starts. Do you see the "Security" light flashing on the dash when trying to start it?

[jason.arthur.taylor]

Thanks for the advice.

 

Do you see the "Security" light flashing on the dash when trying to start it?

 

No, as you can see from the video if you look at it at 39 seconds.  (On the left is an instrument "circle".  There is a battery icon there.  Directly above that is the red "security" light.)  It is not flashing when trying to start.  Rather, it is on when all lights turn on to help perhaps indicate which bulbs have burned out and which are good.  Unless that is how vats tells the user the key is bad.  After the initial timeout, the security light goes off.  It is not on when attempting to crank, either.

 

I am curious, Rich, why did you not see the video?  Is the format not working on your browser or something?

[rich_e777]

The video requires downloading and is getting hung up at 32% for me.

[Padgett]

Does act like a VATS. Do you have any white wires hanging under the steering column ?

[Imp558]

the antitheft system can cause it not to turn over, try a 30 minute re-learn procedure:

1) ignition switch to "run" for 10 minutes

2) cycle igition off and immediately to "run" again

3) ignition switch to "run" for 10 minutes

4) cycle igition off and immediately to "run" again

5) ignition switch to "run" for 10 minutes

6) cycle key off and proceed to "start"

 

If this doesn't work try the same procedure with 15 minutes instead of 10. The purpose of the 30 & 45 minute re-learn is to link the BCM & PCM and the link could have been lost if the battery was out, though rare.

[jason.arthur.taylor]

Does act like a VATS. Do you have any white wires hanging under the steering column ?

 

 

 

.

Yes, but as you can see they are more purple and white, like here http://www.ls1lt1.com/forum/car-audio-electronics/35118-how-bypass-your-vats-write-up.html .

 

 

[jason.arthur.taylor]

the antitheft system can cause it not to turn over, try a 30 minute re-learn procedure:

1) ...

 

If this doesn't work try the same procedure with 15 minutes instead of 10. The purpose of the 30 & 45 minute re-learn is to link the BCM & PCM and the link could have been lost if the battery was out, though rare.

 

But the security light would need to be on, right?  (It isn't.)  

 

EDIT:  Oh, wait, I get it.  You are saying if the century bcm isn't talking to the pcm then that would explain the issue.  Well.  I did this procedure.  I think.  Although man it is difficult.  There wasn't any chance I don't think.

[Padgett]

OK, big purple is usually the starter solenoid, on a stick car the clutch safety switch is often jumpered out (otherwise cannot crank off a railroad track).

 

Perhaps a picture of your key would help, did they still use the VATS in '00 ? (have a '90 that does but the GTP does not)

 

In the film all of the lights come on but did not hear anything like a solenoid click so would match an anti-theft device in operation.

 

This is a VATS key - the flat blade in a black insulator on both sides is the resistor.

 

Edited June 14, 2016 by Padgett

[jason.arthur.taylor]

Yes it uses two keys. One for the door and one with a resistor for the ignition.  Like I said, that is how the passkey II edition of gm's vats works.

[Padgett]

OK well there is a section in the FSM - should be at 8A-133. Here is the schematic from my '90.

 

 

[jason.arthur.taylor]

OK well there is a section in the FSM - should be at 8A-133. Here is the schematic from my '90.

 

 

 

Well in the II edition they removed the passkey unit and included it as part of the bcm module, which sends the same 50hz A-OK signal to the main computer (ecu?).  At any rate, since I do not have a blinking security light in the movie, I bit the bullet and purchased the gear to safely raise up the car so we will have starter power hotness or coldness data soon.

[jason.arthur.taylor]

Imp558 and rich_e777, 

 

The car starts if I hotwire the solenoid to the positive terminal of the battery.  It dies as soon as I remove power to the solenoid or after about 2-4 seconds.  

 

I already did that relearn procedure.

 

Using advanceautoparts I get a part # of BUICK 9388970 Electronic Control Unit

 

• Main Info
• Application
• Interchange Parts

BUICK 9388970

Descripition

Brand:BUICK Part Number(s):9388970 ProductName: Electronic Control Unit

Cross Interchange Parts

Factory Number CARDONE 73-8970 GM 16257051 GM 9388970 BUICK 16257051 BUICK 9352601 BUICK 9389411
 

 

This implies that these parts are indeed compatible BUT advance auto parts says,

Product Application(s):

2000 Buick Regal

• Remanufactured Body Control Computer; with OE # 9388970; Units must be flashed ON the vehicle.  Vehicle specific on-car programming must be performed AFTER install to prevent drivability issues

What does this mean?  Do I need to flash this to get it to work?

 

What is the next step?  

[jason.arthur.taylor]

Here is a circuit diagram just for the starting circuits:

 

Does anyone have any idea what is means if the gas gauge goes from empty to full when I turn the on the "on" position and then, after like 40 seconds, it goes to empty!  Then a few more seconds later, the gas empty light goes on!

[Imp558]

I would try to find a used BCM and do the re=learn procedure from earlier.

[jason.arthur.taylor]

Ok I think I have confirmed it is some sort of vats-related problem.  It turns out my scanner software sucked.  ScanXL is much better and worth every cent.  It says:

 

P1626 (Theft Deterrent Fuel Enable SIgnal Not Received)

U1000 (Class 2 Data Link Malfunction) ECU $10

U1000 (Class 2 Data Link Malfunction) ECU $58

U1064 (Lost communications with Body Multiple Control System) $58

 

Anyone know why there are two U1000 codes?  Does this mean both the bcm and the pcm (or ecm) are complaining about not being able to talk?

 

There are three unplugged wires in the cabin. One is for fog lights but the others I don't know about.  Perhaps that is related.

 

[Imp558]

do you have a diagram showing the anti-theft system?

 

If I remember correctly that's Passkey III, which means no 50hz signal but instead a coded datastream from the BCM to the PCM. It would be feasable that with the U1064 present there is no comm with the BCM. My next step would be to snag a BCM from a yard and do the re-learn procedure you did the other day but this could also be a poor or open connection on the data bus or as simple as a blown BCM fuse so it would be a good idea to have prints or a BCM pinout and verify stuff with a meter before you buy anything.. For the record I've never personally seen a BCM fail.

Edited June 19, 2016 by Imp558

[Padgett]

Well if the tach also swings to max and back then is part of the POST (Power On Self Test).

 

Also looks like the U1000 is being reported by two different tests/modules, $10 and $58 ($ means this is a hexadecimal number). I do not have any GM car that late so do not know exactly what tests those are.

[jason.arthur.taylor]

do you have a diagram showing the anti-theft system?

 

Your wish is my command.

 

 

 

"If I remember correctly that's Passkey III, which means no 50hz signal but instead a coded datastream from the BCM to the PCM. "

 

No this is passkey II.  I think it has to be a 50hz signal.  Correct if I am wrong.  I think the main difference has to do with the resistor vs. wireless tech?

 

"My next step would be to snag a BCM from a yard and do the re-learn procedure you did the other day but this could also be a poor or open connection on the data bus or as simple as a blown BCM fuse so it would be a good idea to have prints or a BCM pinout and verify stuff with a meter before you buy anything.. For the record I've never personally seen a BCM fail."

 

I purchased a fresh BCM off of ebay for $20 and it should arrive by Tuesday.  But my guess is that it is that is will not fix the problem.   My guess is that the U1000 code means that a prior owner, in trying to defeat VATS, cut a wire or broke a wire in the many wire harnesses.  I guess I should take a picture but there seem to be too many unconnected things around.  I saw an antivats video on ebay where they had to cut a yellow wire.  My feeling is that someone cut some wrong wires.  But the other possibility is that U1000 is a very general flag that is triggered anytime a subcode (according to this theory) like P1626 is activated.  If P1626 is normally coming with U1000 then this theory is correct.  But, I don't think it is.  I think U1000 is saying there is another problem.  I hope someone who knows more about U1000 posts.  I my google "U1000 vats" to see more about what others have posted.

 

Thanks so much for your help Imp558. 

Padgett: "Well if the tach also swings to max and back then is part of the POST (Power On Self Test)."

 

Realize the car cannot start by itself yet.  But, the car started normally while I had power to the solenoid, including revving it up once.  But I didn't want to hurt the starter motor so we cut power after a few seconds.  

Thanks again.

 

"blown BCM fuse"

 

I think all the fuses are located above the passenger-side front wheel well strut tower.  I checked each one.  One relay was bad.  I replaced it.  But is there any other place to check for bad fuses or relays?  There was one relay with 5 terminals under the glove compartment.  But, only 4 wires are going out of it.  

[Imp558]

okay, now you need to unplug the BCM and verify those 6 wires. Power, ground, resistance across the key and continuity on the data bus to the PCM. (Always disconnect the battery when unplugging a PCM). If everything checks out hit a yard and get a BCM with the matching key. Read the key resistance and substitute a resistor for the key or use the whole ignition switch out of the donor vehicle in the car so you can use the key. Alternatively you could have the PCM programmed to remove the VATS and do a more permenant bypass on the start relay.

[Padgett]

Or just connect a resistor with the proper value across the two whites but first I'd just jump the yellow-black to ground and see if it cranks.

 

BTW I suspect that ABGM is a cover with jumpers - looks like the old ALDL. If it is a removable cover that might be your problem.

[jason.arthur.taylor]

Or just connect a resistor with the proper value across the two whites but first I'd just jump the yellow-black to ground and see if it cranks.

 

BTW I suspect that ABGM is a cover with jumpers - looks like the old ALDL. If it is a removable cover that might be your problem.

 

What do you mean by ABGM and ALDL?  Air Bag by General Motors?

 

Here are the three unconnected connectors under the dash:

 

 

The big two bottom ones plug into the plastic paneling and one of those is labelled "fog lights".  The other of the two big ones connects into a dummy plug.  The plug I do not know about is the two-wired one with one green and white wire and one black wire.  Does anyone know what that goes to?   It is this plug which makes me wonder if changing the bcm will work.  

 

I guess I could verify that the resistor bank is connected but here is the thing.  Doesn't the relearn procedure automatically set the resistance comparison value into the BCM?  If not, perhaps I need to try all those resistor values again.  It took a while since I have to wait a few minutes perhaps that was the problem.  Perhaps the relearn procedure doesn't set the resistor value.  By the way the proceedure takes 33+0.5*3 minutes.  (11 x 3 times waiting with on, 3 times waiting 30 seconds off.  Not 10 x 3.) Does anyone know?

[Padgett]

No, if you go up the schematic above the BCM in post 19 you see "Splice Pack S205". The jumpers (cover ?) needs to be on it.

 

If that is the BCM dangling then the white/black and purple/white wires may be on it. They are not big wires.

 

ps that was the wires going to the splice pack. Assembly Line Data Link is the old GM serial bus.

Edited June 20, 2016 by Padgett

[jason.arthur.taylor]

Hmm.  That is funny looking at the #19 schematic.  The dark green wire into the pcm is the same color as the one that is unconnected, and pictured.  

 

Wow.  I discovered a second unconnected and unknown connector.  Here it is.  

 

It is right near the ignition harness connector (right of steering column under dash.)  Any idea where this connects?  Or what it does?  My guess is that if I can get these two connectors connected that would fix "the U1000 (Class 2 Data Link Malfunction) ECU $58" error.  Or I could be wrong and they go to the stereo.  I guess I could test all the stuff in the car and see what is not working to rule other stuff out.  Or use the color of the wires to compare to the diagrams.  

[Imp558]

or you could just check the wires that you know beyond a doubt in that schematic and see if there's a problem with a connection....