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-   -   won't crank vats (https://www.corvetteforum.com/forums/c4-tech-performance/3205614-wont-crank-vats.html)

prestige6 01-23-2013 03:43 PM

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

WVZR-1 01-23-2013 03:59 PM


Originally Posted by prestige6 (Post 1582923641)
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!

prestige6 01-23-2013 04:02 PM


Originally Posted by WVZR-1 (Post 1582923781)
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..

vetteoz 01-23-2013 04:11 PM


Originally Posted by prestige6 (Post 1582923806)
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

leesvet 01-23-2013 04:11 PM

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.

WVZR-1 01-23-2013 06:47 PM

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!

prestige6 01-24-2013 12:03 PM


Originally Posted by leesvet (Post 1582923888)
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..

WVZR-1 01-24-2013 12:24 PM


Originally Posted by prestige6 (Post 1582931409)
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

prestige6 01-24-2013 12:39 PM


Originally Posted by WVZR-1 (Post 1582931603)
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...

WVZR-1 01-24-2013 01:10 PM


Originally Posted by prestige6 (Post 1582931764)
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.

prestige6 01-24-2013 02:11 PM


Originally Posted by WVZR-1 (Post 1582932103)
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

WVZR-1 01-24-2013 02:41 PM


Originally Posted by prestige6 (Post 1582932618)
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!

prestige6 01-24-2013 04:10 PM


Originally Posted by WVZR-1 (Post 1582932872)
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

prestige6 01-25-2013 06:47 PM


Originally Posted by WVZR-1 (Post 1582932872)
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???

WVZR-1 01-25-2013 07:28 PM


Originally Posted by prestige6 (Post 1582945168)
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!!!

prestige6 01-25-2013 07:28 PM


Originally Posted by WVZR-1 (Post 1582945420)
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

prestige6 01-26-2013 11:14 AM


Originally Posted by WVZR-1 (Post 1582945479)
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.......


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