C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

won't crank vats

Old 01-23-2013, 03:43 PM
  #1  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default won't crank vats

Reason I'm here I hope all GM vats systems are pretty much the same. I just bought a 95 caddy deville,was running fine,now won't crank. Read up on the vats system and measured the resistance in the key came up with 9.49K went to radio shack got 2 4.7 resistors cut the orange lead that comes from the ign. switch put the resistor between the two white wires in the Orange sleeve. Still No Crank.. Any advise what to do next.. Thanks
Old 01-23-2013, 03:59 PM
  #2  
WVZR-1
Team Owner

 
WVZR-1's Avatar
 
Member Since: Sep 2003
Posts: 23,045
Received 2,254 Likes on 2,017 Posts

Default

Originally Posted by prestige6
Reason I'm here I hope all GM vats systems are pretty much the same. I just bought a 95 caddy deville,was running fine,now won't crank. Read up on the vats system and measured the resistance in the key came up with 9.49K went to radio shack got 2 4.7 resistors cut the orange lead that comes from the ign. switch put the resistor between the two white wires in the Orange sleeve. Still No Crank.. Any advise what to do next.. Thanks
You have them in a series "end-to-end"? Depending upon the tolerance percentage of the resistors you could still fall beneath the "minimum threshold" for the resistance values! Did you check the resistors before installing? Do it now! If they were 10% resistors you could be well below the threshold, 10% high and it's well out high. Actually 5% resistors could also.

I see posts on the Cadillac Forum and here! Are those the only two? Likely not!

Last edited by WVZR-1; 01-23-2013 at 04:09 PM.
Old 01-23-2013, 04:02 PM
  #3  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
You have them in a series "end-to-end"? Depending upon the tolerance percentage of the resistors you could still fall beneath the "minimum threshold" for the resistance values!
Measured them and it came within the tolerance of 2% also took the other key I have and put the wires on that to act as a resistor still nothing..
Old 01-23-2013, 04:11 PM
  #4  
vetteoz
Safety Car
 
vetteoz's Avatar
 
Member Since: Jan 2004
Posts: 3,556
Likes: 0
Received 10 Likes on 9 Posts

Default

Originally Posted by prestige6
also took the other key I have and put the wires on that to act as a resistor still nothing..
As with any other GM VATS system also you have the starter enable relay operated by VATS which is a possible fault point.
VATS may be reading the key / resistors correctly but if the relay is bad you will get a no crank situation

Simplest test would be to hot wire the starter to crank the engine over.( Key on )
If it fires up (VATS shuts off the injectors ) you know the problem is with the starter circuit ie;
Ign switch , relay , P/N switch or the wiring itself to the starter solenoid
Old 01-23-2013, 04:11 PM
  #5  
leesvet
Safety Car
 
leesvet's Avatar
 
Member Since: Apr 2011
Posts: 3,660
Received 20 Likes on 14 Posts

Default

That key switch is not the only part of VATS...

you also have the starter enable relay, which is a common failure and the first place to test the system. What SHOULD be done is test the orange cable with the KEY inserted to ON/RUN and see if there is the same resistance as going across the key pellet. THAT is how you tell if the key switch is working or not. If the resistance is OK< move on the relay then finally to the VATS module. The FSM for any GM car will describe the complete step by step diagnostic for VATS.
Old 01-23-2013, 06:47 PM
  #6  
WVZR-1
Team Owner

 
WVZR-1's Avatar
 
Member Since: Sep 2003
Posts: 23,045
Received 2,254 Likes on 2,017 Posts

Default

The system needs diagnosed in order but if you wanted to jump to parts replacing etc the neutral safety switch is/was a frequent nuisance. You could check the voltages in and out and move forward. With your VATS by-passed can you take 12V to starter and crank? The N/S switch can be very intermittent. Which engine? That adds to the possibilities!
Old 01-24-2013, 12:03 PM
  #7  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by leesvet
That key switch is not the only part of VATS...

you also have the starter enable relay, which is a common failure and the first place to test the system. What SHOULD be done is test the orange cable with the KEY inserted to ON/RUN and see if there is the same resistance as going across the key pellet. THAT is how you tell if the key switch is working or not. If the resistance is OK< move on the relay then finally to the VATS module. The FSM for any GM car will describe the complete step by step diagnostic for VATS.
I tested the Orange lead with the 2 white wires in it from the Ign. key switch.9.49k so this means No Broken Wires.. I was able to pull these codes from the DTC can anyone tell me if they would have anything to do with the No crank,before i go any further....I 052 P 052 I 033 I 039 Thanks..
Old 01-24-2013, 12:24 PM
  #8  
WVZR-1
Team Owner

 
WVZR-1's Avatar
 
Member Since: Sep 2003
Posts: 23,045
Received 2,254 Likes on 2,017 Posts

Default

Originally Posted by prestige6
I tested the Orange lead with the 2 white wires in it from the Ign. key switch.9.49k so this means No Broken Wires.. I was able to pull these codes from the DTC can anyone tell me if they would have anything to do with the No crank,before i go any further....I 052 P 052 I 033 I 039 Thanks..
None appear related! I asked which engine? You've not answered. Did you check N/S switch? No.


http://z-cut.de/US/dtcobd1.html
Old 01-24-2013, 12:39 PM
  #9  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
None appear related! I asked which engine? You've not answered. Did you check N/S switch? No.


http://z-cut.de/US/dtcobd1.html
4.9 motor Didn't check the NSS switch yet,Where's it located.. I'm doing this outside and it's so Friggen Cold...
Old 01-24-2013, 01:10 PM
  #10  
WVZR-1
Team Owner

 
WVZR-1's Avatar
 
Member Since: Sep 2003
Posts: 23,045
Received 2,254 Likes on 2,017 Posts

Default

Originally Posted by prestige6
4.9 motor Didn't check the NSS switch yet,Where's it located.. I'm doing this outside and it's so Friggen Cold...
Under-hood at shift selector I believe. You should do much better over where you started on the Cadillac Forum. I'm familiar with the procedure to check but I can't lead you through it.
Old 01-24-2013, 02:11 PM
  #11  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
Under-hood at shift selector I believe. You should do much better over where you started on the Cadillac Forum. I'm familiar with the procedure to check but I can't lead you through it.
I think you are write on the money with the NSS I just jumped the starter and Wala it started. Now when I warm up again I'll test and replace NSS switch .. Thanks
Old 01-24-2013, 02:41 PM
  #12  
WVZR-1
Team Owner

 
WVZR-1's Avatar
 
Member Since: Sep 2003
Posts: 23,045
Received 2,254 Likes on 2,017 Posts

Default

Originally Posted by prestige6
I think you are write on the money with the NSS I just jumped the starter and Wala it started. Now when I warm up again I'll test and replace NSS switch .. Thanks
The NSS isn't inexpensive - do your diagnostics first! Don't just jump in like you did the VATS! Post back!
Old 01-24-2013, 04:10 PM
  #13  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
The NSS isn't inexpensive - do your diagnostics first! Don't just jump in like you did the VATS! Post back!
I know it's around 100.00
Old 01-25-2013, 06:47 PM
  #14  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
The NSS isn't inexpensive - do your diagnostics first! Don't just jump in like you did the VATS! Post back!
Where is the starter relay. Looked all over can't find it.Does the car have one???
Old 01-25-2013, 07:28 PM
  #15  
WVZR-1
Team Owner

 
WVZR-1's Avatar
 
Member Since: Sep 2003
Posts: 23,045
Received 2,254 Likes on 2,017 Posts

Default

Originally Posted by prestige6
Where is the starter relay. Looked all over can't find it.Does the car have one???
You'll love this one. I believe it's taped to the body harness in the vicinity of the drivers "kick-panel" maybe more towards the the rocker. This link should work for you:

http://ww2.justanswer.com/uploads/JF...95_deville.pdf

Remove the sill plate and pull carpet back. I don't believe it that tough once you know you're looking in the proper area. The rest of your relays and maybe the theft deterent is maybe in the trunk attatched to the left side of the rear seat.

Enjoy!!!
Old 01-25-2013, 07:28 PM
  #16  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
You'll love this one. I believe it's taped to the body harness in the vicinity of the drivers "kick-panel" maybe more towards the the rocker. This link should work for you:

http://ww2.justanswer.com/uploads/JF...95_deville.pdf
I just found that link also. I checked the NSS and it tests good,so I'm leaning towards the fuse in the trunk or the relay..See what tomorrow brings... Thanks
Old 01-26-2013, 11:14 AM
  #17  
prestige6
Melting Slicks
Thread Starter
 
prestige6's Avatar
 
Member Since: Sep 2006
Posts: 3,139
Received 90 Likes on 59 Posts

Default

Originally Posted by WVZR-1
You'll love this one. I believe it's taped to the body harness in the vicinity of the drivers "kick-panel" maybe more towards the the rocker. This link should work for you:

http://ww2.justanswer.com/uploads/JF...95_deville.pdf

Remove the sill plate and pull carpet back. I don't believe it that tough once you know you're looking in the proper area. The rest of your relays and maybe the theft deterent is maybe in the trunk attatched to the left side of the rear seat.

Enjoy!!!
I'll be damned,but I can't find that relay.......

Get notified of new replies

To won't crank vats



Thread Tools
Search this Thread
Quick Reply: won't crank vats



All times are GMT -4. The time now is 03:15 PM.