Sudden VATS Trouble ????
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
Thanks, found a Mitchell FSM for 91 GM cars. Wiring diagram shows starter enable relay and four wires, 2 Yellows, Black/Yellow stripe, and Yellow/Black stripe.
Is this located in the same spot on a 91 as the 87, and what wires would I jump. Both yellows go to ignition, Black/Yellow stripe goes to CCM, Yellow/Black stripe goes to clutch switch.
Is this located in the same spot on a 91 as the 87, and what wires would I jump. Both yellows go to ignition, Black/Yellow stripe goes to CCM, Yellow/Black stripe goes to clutch switch.
if does not you are back to ign switch.
Heel & Toe
Joined: Jul 2011
Posts: 17
Likes: 0
Cool. 1 is Yellow and 4 is Yellow/Black stripe. Now I need to find the SER
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
Sammy,
I almost mentioned this a day or two ago but, well...got shy. I just re-read the entire thread and still think this may be relevant, though, so here goes:
In my '87 when the VATs triggers it disables ignition and either the injectors or fuel pump (not sure which) but the starter still cranks. In your case the starter isn't cranking & that makes me think it's not VATs but one of the other issues you've been investigating.
Not much help, I know, but may help you focus your efforts.
Wayne
P.S. my VATs triggered the other night & I had to sit there in the dark like a dope through two 4 minute cycles before I got my key in just the right position & was able to start. Glad that doesn't happen often.
I almost mentioned this a day or two ago but, well...got shy. I just re-read the entire thread and still think this may be relevant, though, so here goes:
In my '87 when the VATs triggers it disables ignition and either the injectors or fuel pump (not sure which) but the starter still cranks. In your case the starter isn't cranking & that makes me think it's not VATs but one of the other issues you've been investigating.
Not much help, I know, but may help you focus your efforts.
Wayne
P.S. my VATs triggered the other night & I had to sit there in the dark like a dope through two 4 minute cycles before I got my key in just the right position & was able to start. Glad that doesn't happen often.
Heel & Toe
Joined: Jul 2011
Posts: 17
Likes: 0
Burning Brakes
Joined: Dec 2008
Posts: 1,021
Likes: 7
From: Morgan Hill and Marina California
Sammy,
I almost mentioned this a day or two ago but, well...got shy. I just re-read the entire thread and still think this may be relevant, though, so here goes:
In my '87 when the VATs triggers it disables ignition and either the injectors or fuel pump (not sure which) but the starter still cranks. In your case the starter isn't cranking & that makes me think it's not VATs but one of the other issues you've been investigating.
Not much help, I know, but may help you focus your efforts.
Wayne
P.S. my VATs triggered the other night & I had to sit there in the dark like a dope through two 4 minute cycles before I got my key in just the right position & was able to start. Glad that doesn't happen often.
I almost mentioned this a day or two ago but, well...got shy. I just re-read the entire thread and still think this may be relevant, though, so here goes:
In my '87 when the VATs triggers it disables ignition and either the injectors or fuel pump (not sure which) but the starter still cranks. In your case the starter isn't cranking & that makes me think it's not VATs but one of the other issues you've been investigating.
Not much help, I know, but may help you focus your efforts.
Wayne
P.S. my VATs triggered the other night & I had to sit there in the dark like a dope through two 4 minute cycles before I got my key in just the right position & was able to start. Glad that doesn't happen often.
happens, like a completely dead battery. No crank, no nothing.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
joking, of course, but 'nothing' means somethng different to everyone, for example, dash lights on, fuel relay clicking, FP running 2 secs, to someone expecting the starter to run, means nothing happened. but vats is not supposed to disable everything. so my e-bay fsm says.
to me, 'nothing" means waving my key at the car.
joe
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Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
Oh, well. Hopefully, Sammy is well enough along in his research my little thought is irrelevant. (I think I'll take a look in my FSM tonight though, just out of curiosity.)
Yikes! Maybe this means my occasional starting problem isn't VATs!?!?!?!
Last edited by 3D87C4; Jul 22, 2011 at 06:15 PM. Reason: Yikes
Thread Starter
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
hey just came back from the car ...found out that i was cranking the car with the doors open ...when i put the key on "RUN" position ...no security light at all .-
I toook the cap off the relay and i pushed the little metallic tab to make contact
near the inner coil and it cranks !
my whole bets are on the starter enable relay.
I toook the cap off the relay and i pushed the little metallic tab to make contact
near the inner coil and it cranks !
my whole bets are on the starter enable relay.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
hey just came back from the car ...found out that i was cranking the car with the doors open ...when i put the key on "RUN" position ...no security light at all .-
I toook the cap off the relay and i pushed the little metallic tab to make contact
near the inner coil and it cranks !
my whole bets are on the starter enable relay.
I toook the cap off the relay and i pushed the little metallic tab to make contact
near the inner coil and it cranks !
my whole bets are on the starter enable relay.
joe
Heel & Toe
Joined: Jul 2011
Posts: 17
Likes: 0
hey just came back from the car ...found out that i was cranking the car with the doors open ...when i put the key on "RUN" position ...no security light at all .-
I toook the cap off the relay and i pushed the little metallic tab to make contact
near the inner coil and it cranks !
my whole bets are on the starter enable relay.
I toook the cap off the relay and i pushed the little metallic tab to make contact
near the inner coil and it cranks !
my whole bets are on the starter enable relay.
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
Huh. I wonder why it would be different car-to-car?
Oh, well. Hopefully, Sammy is well enough along in his research my little thought is irrelevant. (I think I'll take a look in my FSM tonight though, just out of curiosity.)
Yikes! Maybe this means my occasional starting problem isn't VATs!?!?!?!
Oh, well. Hopefully, Sammy is well enough along in his research my little thought is irrelevant. (I think I'll take a look in my FSM tonight though, just out of curiosity.)
Yikes! Maybe this means my occasional starting problem isn't VATs!?!?!?!
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
On the '87 VATS has two outputs. One turns on the crank relay. The other output goes to the ECM. When the ECM sees this signal it turns on the injectors.
On later cars the VATS module also has an output to the SECURITY light. I don't know what year added that.
On later cars the VATS module also has an output to the SECURITY light. I don't know what year added that.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
I hope this is a HEHEHE!
I remembered that the fsm 8a 30 4 says that IF the relay can be jumpered to crank, check VATS. It has apparently interrupted the y/blk wire in the relay. Not sure the science of it, but...still a VATS issue.
"so say the bird," as the street magician would say.
*** my fsm is 91, the 87 is maybe different, not sure they has a CCM, but they had the vats module.
joe
Last edited by joe paco; Jul 23, 2011 at 07:35 AM. Reason: add ***
Instructor
Joined: Jun 2011
Posts: 182
Likes: 0
From: Bowling Green Ky
on CCM cars, you can check relays via grnding terminal a-g, have done it many times and can hear the relays click -also horn works for 3 secs.
somewhere in this mess of computer "disabling" I read where the air bag fuse should be verifed, on 91 at least.
jc
Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
In my '87, when the VATS kicks in, you turn the key and nothing
happens, like a completely dead battery. No crank, no nothing.
happens, like a completely dead battery. No crank, no nothing.
Vats disables crank!!!!!
I'll check for codes 46 or 54 later today. My problem is intermittent, occuring only 3 times since I got the car last November, and recovers after the typical 4 minute wait so I'm inclined to think it is VATs related. I have other plans for this car that will likely disable the VATs so am inclined to live with this unless it stops recovering by itself.
Sorry to have cluttered this thread. I'll start a seperate thread if I need further help.
Update:
I checked and no codes are stored. I have one question about that and have initiated a seperate thread
http://forums.corvetteforum.com/c4-t...post1578213371
Last edited by 3D87C4; Jul 23, 2011 at 05:17 PM. Reason: update: no codes found new thread initiated
Thread Starter
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
Sammy
I hope this is a HEHEHE! I remembered that the fsm 8a 30 4 says that IF the relay can be jumpered to crank, check VATS. It has apparently interrupted the y/blk wire in the relay. Not sure the science of it, but...
still a VATS issue.
"so say the bird," as the street magician would say.
*** my fsm is 91, the 87 is maybe different, not sure they has a CCM, but they had the vats module.
joe
I hope this is a HEHEHE!
I remembered that the fsm 8a 30 4 says that IF the relay can be jumpered to crank, check VATS. It has apparently interrupted the y/blk wire in the relay. Not sure the science of it, but...still a VATS issue.
"so say the bird," as the street magician would say.
*** my fsm is 91, the 87 is maybe different, not sure they has a CCM, but they had the vats module.
joe
Joe to tell you the truth,im just rolling the dice
i bought the starter enable relay yesterday (maybe mine was good but maybe not) and im waiting for it to arrive.
Maybe i do have a VATS issue.
There is a test i didn't do ...test the actual VATS MODULE
its a hell to get there ! i couldn't remove the breadbox.
Well, on FSM suplement 8A-133-11 i got to the Starter enable relay test
and everything was fine until "C2" and i used a jumper wire to "E" Yellow wire and "A" "Green/white wire". and Car's ALIVE !!!!!! Cranked like a champ !!!
That leaded me to another step : "C3" and i will quote the FSM here :
" Reconnect the starter enable relay amd connect a fused jumper from terminal "V"
(dk green) wire of the VATS Decoder module to ground . Turn ignition switch to start.
if engine cranks : replace the VATS Decoder module
if engine doesnt crank : check the Green wire for open,if its ok,replace Starter enable solenoid.
Its one or another, i hope its the relay !
