First, this is an 88 4+3 convertible I purchased that had been slightly hit in the rear and badly neglected electrically. After several months of body repairs and electrical fixes--everthing works except I get a no crank when keying into the "start" position? I am in the midst of troubleshooting things but VATS can be a painstaking affair! My immediate question is this: where is the "STARTER ENABLER" located and are there any checks which tells if the ENABLER, THEFT MODULE AND THEFT CONT MODULE are bad?

Currently testing wire circuits for continuity/voltage. I may find the problem by the time someone responds but things are driving me whacky right now. I am hoping that the resistance key, resistance pellet and starter decoder are all the same--how would you really test this too? Bill Texas I could drive this thing if I could get it started!!!!!!!!!!!!

 

Can't answer your question...jfb will probably pop in with the answer, I did away with the factory alarm and went with after market...best thing I did. Here's a couple things..first if you have another key, try it, clean the key with rubbing alcohol, then try.Make sure the key lock on the outer door is straight up and down..if the key comes out of the door lock at an angle you'll have an alarm problem.

 

Mid America, Corvette America, both sell a vats by-pass module if you would like to eliminate that problem. Mid America item #601-116 $26.99

 

Don't waste your money jfb can tell you how to simply do it with a resistor from radio shack..has to do with measuring the resistance between the two VATS wires coming out of the bottom of the steering column, going to Radio Shack getting a resistor I think of the same value and installing it between the two wires.Better wait for him though, I'm just going by my weak memory...which could be wrong.

 

Most likely VATS, but first unplug the clutch safety switch, jump the socket bypassing it and try a crank (defective clutch safety sw). If no crank, then put a voltmeter from the jumper to ground and try a crank. If you have 12v and no crank, then you have a battery, battery connection, starter connection, or starter problem. If no 12v, then remove the hush panel above the drivers feet and find the 2 wires from the steering column that go to a 2 pin connector and unplug. Insert your ign key and measure the resistance across the wires from the steering column. It should be the same as the pellet and if over 13k ohms, then you need a new ignition tumbler that has new contacts that make connection to the pellet. You can temporarily bypass VATS by connecting a 1/4W 5% resistor the same value as your pellet across the 2 pin socket (goes to VATS module). You can buy the resistor from Radio Shack but you may have to measure several to get a value that is close enough. Don't permanently bypass VATS because 99% of thefts are done by bashing the column and jumping the ignition.
The start enable relay is located behind the instrument panel about in the center in what looks like a plastic box with no cover called the ,"multi-use center".
The theft module doesn't prevent a start, only the VATS module does.
If you have the correct resistance on the wires going the VATS module and the start enable relay won't close, but the relay is good, then you have a defective VATS module. If you need any further help, let me know.

 

Appriciate everybody's input on this. My problem is that I rescued this really cheap ($2K) but very solid 88 convertible from a small rear hit, poor electrical upkeep and a lousy C5 conversion attempt. I restore all my own cars so this one got a conversion back to original body style. I have five corvettes and I like them "ORIGINAL" with everything working correctly. So, stupid as it may be, I have just got to have the VATS work the way it is suppose to. Ignorant--I Know but I cannot help it.

Since my initial post, studying wire diagrams helped stupid me figureout that the "enabler" is the "relay" in the Center Panel area. I also figured out that the theft controller primarily affects the door locks--assuming the door systems check out, then none of it should really affect the "cranking" part. I get good voltage at all the fuse connections (Theft, VATS, Ignition, etc)

The meat of the issue for getting juice to the starter solenoid to crank is for the ignition switch "SOL" pole in the start position to send 12 volts to the "relay". At the same time, the Key resistance is checked at the "theft module cavity "U and T" and if okay another voltage is also sent to the relay cavity B which then allows relay current to be sent to the "neutral safety" to the bulkhead connector and then to the solenoid. All working properly-----the starter should crank (but not in my case yet).

I will tackle this affair one more time tomorrow and I need to make sure that all my door stuff is functioning correctly, or that the tumbler issue isn't the problem, or that the "decoder" is bad, or that my resistance items are mismatched, or that . . . I WILL NAIL THIS DOWN YET!!!!

Thanks again so much. I know these type questions and verbose replies suck. I just needed some advice and I had to get it off my chest. Belton, Texas

 

If you need any further help, just ask, I am always willing to help!

 

jfb, good to know you are out there! Hopefuly tomorrow will be an enlightened day for me and you won't be needed? Sorta like an ex-wife. I didn't really mean that for you. Thanks and nothing further for now. Bill

 

have you jumped starter to see if it works? your post didnt say

 

Spinball, No. Don't know if you have ever tried to work on a convertible but if you have--you simply cannot get to several areas without terrific discomforts. Since my original post I found that the temp guage engine side wire was rewired to the cooling aux fan relay, the temp guage was wired to the coolant low sensor, the temp guage wire was cut and hiding on top the converter, and the right side cylinder head temp sender hole was plugged and the plug seized! So, I skipped pursuing "no crank" issues for the moment. Today I am drilling out the head plug but--lots has to come off to get to the plug!!!!!!!!!! What an effort. And, I have corrected all the other miswired things and should be able to reach the 1/8 inch length of temp guage wire that you cannot work on because of things in the way. Lot of info for you on simply asking is I tried the direct starter test--Hope to do this soon but I know I can get her going now. Lots of things are working that never worked before. Bill

 

Something doesn't seem right. The temp gauge sender should be in passenger head and the aux fan switch should be in driver side head. A plug in the passenger side head Sounds like the motor or heads are not original.

 

Agent, the previous owned indicated he had had the motor rebuilt? That scares me too! I did drive this car from Austin to Belton which is about an hour trip when I purchased it. It actually ran pretty good but the radiator seal was bad and it would attempt overheating as coolant leaked out. Many stops that day adding coolant but I got home. And, I remember that the temp gauge didn't work and I had to kinda go by the oil temp gauge. Anyway, I currently have the aux fan switch in driver head and the passenger side plug removed and a new temp sender in it. This is the way it is suppose to be. I actually believe that the original sender wire which was cut just got lost in their rebuild and they overlooked it!!!!!!!!!!! So, the easy way out for them was to just plug the head. You have to realize that much of the front harness had been whacked to accomodate his attempted C5 conversion.

Incidently, I removed all the evaporator stuff and had to drill the plug out--took a 1/2 inch hole before an easy out would start working!!!!!! Was getting really close for me. As of this moment I have completed a reconstruction of the rear tub, replaced a corner section of the rear RH fender, replaced the rear frame cross-member and back 7 inches of RH frame rail, professionally had rear frame moved about 1/4 inch to get frame correct, repaired/troubleshoot everything, replaced both front and rear bumper to original and now in "no crank" condition. As soon as I figure out how to get to and replace the Neutral Safety Switch on top of the clutch pedal I think she will crank (will use a jumper on connector test as Jfb suggested). The entire wire circuit checked out except for this switch.

The car probably sounds like a mess but she cleaned up well. The car is really, really starting to shape up--new top and paint this December and she will look great! I have been doing all this while I have my 58 and 72 convertible in full body off restoration too. Good thing I don't have to go to work????????????? All is very well now. Bill

 

Sounds like Kaos was invovled

 

This thread is closed for me. After a few checks and a little work, turned the key and she started!!!!!!!!!!!!!!!!!!!!!!!! On my third beer in less than 6 minutes so good night. Bill