Pellet resistance question

[T.M.808]

Aloha gang,
I measured the resistance on both my ignition keys. 11.79ohm and 11.89ohm. Would this be considered a #11 or a #12. I need to buy a matching resistor at radio shack. Not sure which to get.
Thanks.

 

[TedC]

Can you verify your readings? Not aware of any key pellet used by GM that is that low. If you are trying to build a "VATS bypass", understand that is a very misleading name. All you are bypassing is the ignition contacts. I had a VATS starter enable relay go bad, and the so called VATS bypass would have done nothing to change the situation. Here are all the key numbers and associated resistance.

VATS Code -- Resistance

1 -- 392 ohms
2 -- 523 ohms
3 -- 681 ohms
4 -- 887 ohms
5 -- 1.13k ohms
6 -- 1.47k ohms
7 -- 1.87k ohms
8 -- 2.37k ohms
9 -- 3.01k ohms
10 -- 3.74k ohms
11 -- 4.75k ohms
12 -- 6.04k ohms
13 -- 7.50k ohms
14 -- 9.53k ohms
15 -- 11.80k ohms

 

[T.M.808]

Good info, yes i'm trying to build a bypass. Props to member boomdriver Yep,just checked again,got 11.86 on the newest key. So looks like a #15. What resistor should i use? I'm chasing a intermittent no crank, which has turned into, rarely a crank.lol Turn key,all lights and everything come on,turn key, nothing. This has happened mayve 10 times over 6 months, usually, i just turn the key off,the back on and it started. The other day, just never cranked over. New starter,good battery voltage, fusable links all good. Today going to clean all the grounds, ecm too, waiting for my buddy to return my manual and bring the auto xray scanner over morning so i can see where the main ignition switch is,check the wires at the back off the fuse box. Interesting, where is the relay you had to change? On the firewall?
Thanks for the info.

 

[TedC]

Check to make sure you don't have any open recalls. GM had issues with the early ignition switches with weak contacts. Make sure the key is not worn. So it looks like you have 11,800 ohms (11.8K) not 11.xx ohms. You can buy an assortment of resistors and combine them to hit the magic target. Say 10,000 + 1,000 + 500 + 100 + 100 + 100. Double check with VOM.

 

[T.M.808]

My bad, i had the meter set on the wrong "range" setting.
Where is the vats starter enable relay located. I'm leaning toward this,or the key switch. The vats bypass is a last resort. I don't think i need the bypass, because when i got most of the no crank conditions, i didn't have to wait the 6+ mins for the vats to reset. I would turn key... nothing. Turn key off. Immediatly turn key... would fire rite up. Weeks go by without it happening. Now it's a real issue. I'd like to check the enable relay. The other day, i drove the car to about 6 places. Cranked and fired normally. Then blam,get in nothing... So basically i'm going to try and trouble shoot the ignition system today.

 

[TedC]

The starter enable relay is in the center behind the vents. If I remember correctly, I had to remove the top dash panel, not just the center panel. On my 1988, engine start was intermittent. The issue was not ignition contacts, so the so called VATS bypass would of been of no value. The VATS controller is expecting a specific resistance, does an internal compare, if they match, it sends power to the starter enable relay, which if working right, energizes the starter relay.

 

[Curious George]

Check to make sure you don't have any open recalls. GM had issues with the early ignition switches with weak contacts. Make sure the key is not worn. So it looks like you have 11,800 ohms (11.8K) not 11.xx ohms. You can buy an assortment of resistors and combine them to hit the magic target. Say 10,000 + 1,000 + 500 + 100 + 100 + 100. Double check with VOM.

Adding single resistors to get the value you need is the best way to do it. The "assembled" value needs to be fairly close to the original value in order for the vehicle to start repeatedly and reliably.

CG

 

[T.M.808]

Thanks guys.
Since the starter is new, the fusable links,posts and grounds are all good, i'm using the spare key which is like new,lots of meat on the pellet, i'm thinking it's that relay behind the dash. I think i'll tear into to it and jump the relay and see what happens. I really don't think it's the VATS, just was gathering the info as a last resort i'll make the bypass.
Mahalo. :cool

 

[TedC]

I had the dash apart waiting for the condition to happen. Manual, VOM and jumper wire in hand. Took just two days. When it occurred I could see that the VAT controller was sending power. Jumpered the relay, and I was off to the races. You can order the part from a Chevy dealership. It was not very expensive.

 

[T.M.808]

ThanKs. Since i'm going to keep the car ( it will be a monster), i'm thinking if i have to tear behind the dash to get at the relay, i might as well just replace it when i'm in there. Only thing, my manual is a Haynes. Crappy, they don't even mention the main ignition switch or the enable relay. Theres a pic of the turn signal relay and a few next to it, not sure which relay it is.
I can test my relay now, because my intermittent no crank condition, has gone to a rarly crank/start condition.lol.....hasn't cranked over yet today. Tried twice. Car started and ran fine a few times the other day, then back to no crank :W
wonder if theres a radio shack cross reference number... i'm sure the dealer here will have to order it from the mainland.

 

[vetteoz]

wonder if theres a radio shack cross reference number... i'm sure the dealer here will have to order it from the mainland.

Save your $$ and just bypass the relay.
VATS still takes out the injectors so no one can start the car anyway
Any 30A relay would do the job if wired correctly

 

[roger longman]

Wow oz, You know your stuff. My electrical knowledge is just about restricted to screwing in a light bulb......Roger.

 

[boomdriver]

Thats a great fact to know !
Too many folks disable their VATS over the starting issues when they could just bypass the relay. If the system still stops the injectors, thats great. Let some POS car thief sit there cranking on it until I can aim.....

 

[T.M.808]

Save your $$ and just bypass the relay.
VATS still takes out the injectors so no one can start the car anyway
Any 30A relay would do the job if wired correctly

kool.. i'll be able to bypass it with this diagram. I just have to make sure i get the right relay behind the dash.lol. I got the part number in another thread, so i can identify it by that.
Today i just jacked up the car,removed,cleaned and reinstalled the grounds on the bellhousing,block and rail by the battery. Tried to start car, nothing,give the fuse box a good shake, turn key 30 seconds later, car has started 4 times in a row since then. Coincedence? Not sure..lol..
Thanks for the diagram..:cool

 

[T.M.808]

Thanks to all. I learned alot from this thread,and boomdriver as well. I'm going to keep driving until it doesn't start again, then i'm going after the relay. Which will probably turn out to be tomorrow.lol..

 

[T.M.808]

Thanks to all. I learned alot from this thread,and boomdriver as well. I'm going to keep driving until it doesn't start again, then i'm going after the relay. Which will probably turn out to be tomorrow.lol

 

[vetteoz]

I just have to make sure i get the right relay behind the dash.lol. :cool

 

[vetteoz]

Thats a great fact to know
Too many folks diable their VATS over the starting issues when they could just bypass the relay..

Is also were people get confused. Their car cranks but won't fire so they think it can't be VATS problem because engine is cranking over not realising VATS has two components

VATS 101 Essential reading for C4 owners
VATS
VATS and PASSKey Vehicle Anti-Theft Systems - ThirdGen.org

 

[T.M.808]

Awesome.... great pics and info. I'm going to try and figure out how to jumper the relay, as my dealer has to order the part. I read somewere, jumper the yellow and the green/white. Looks like theres 2 of each color in the connector.

 

[T.M.808]

Of coarse this morning the car fired rite up. I went in anyway, opened up the engage relay, cleaned the contacts and reassebled. I left the dash apart like TedC, so when it happens again, i'll be ready, have my jumper wire too. Just have to figure out which wires to jump. Heres how the connector is layed out. I'm guessing green/white stripe, to one of the tan wires.

A
Green/ white wire.
B
Small solid green.
C
Tan
D
No wire.
E
Tan