86 won't turn over
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1st Gear
Joined: Dec 2013
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86 won't turn over
Just got a 86 been sitting for 6 years cleaned the fuel tank and lines change all fluids put a new batt in it doesn't turn over with key can jump starter and it turns over fine when the key is in start position the seceruty lite flashes but no starter need help please.
Safety Car
Joined: Aug 2002
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From: SANTA CRUZ CA
Race Director
Joined: Apr 2002
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From: Anaheim CA
Just got a 86 been sitting for 6 years cleaned the fuel tank and lines change all fluids put a new batt in it doesn't turn over with key can jump starter and it turns over fine when the key is in start position the seceruty lite flashes but no starter need help please.
VATS turns on the starter enable relay and also sends a 30 Hz square wave to the ECM. The ECM will not fire the injectors if it doesn't see that signal. You can tell if this is a problem by reading the error codes. VATS is code 46:
http://forums.corvetteforum.com/1574918379-post18.html
http://corvettephotographs.com/c4vettes/codes.htm
A list of error codes and what they mean is here:
http://forums.corvetteforum.com/1576116036-post35.html
This site has a good explanation of VATS and the various options for defeating or eliminating it:
http://www.joestradingpost.com/vats/
- 1986 Original Owner -
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From: North Yorkshire, England
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It could be a VATS problem, but the SECURITY light has nothing to do with VATS in your car. That's a completely separate system.
VATS turns on the starter enable relay and also sends a 30 Hz square wave to the ECM. The ECM will not fire the injectors if it doesn't see that signal. You can tell if this is a problem by reading the error codes. VATS is code 46:
VATS turns on the starter enable relay and also sends a 30 Hz square wave to the ECM. The ECM will not fire the injectors if it doesn't see that signal. You can tell if this is a problem by reading the error codes. VATS is code 46:
Great info, as usual.
An important fact that Cliff implied, but some may not have understood him completely regarding code 46 on these early VATS cars is that the code is only set if the ECM does not see the square wave signal with the ignition switch in START or RUN. Of the two VATS module functions Cliff describes, only the lack of square wave signal will set the code. If only the enabling ground to the Start Enable Relay is absent, the ECM is not aware and doesn't set the code. Nor can code 46 be set by a failure of the Start Enable Relay or its associated wiring. Circuit 963 is the only connection between the VATS Module and the ECM, so the only criteria for a code 46 on these early VATS cars.
