tony58

Trying to do the On Board Diagnostic on my 1992.I've tried several times by using the paper clip jumping A & B.On the port I attach the clip to A &B turn the switch on.The cooling fan comes on and the check engine light will flash 6 times then 2 times.It does this over and over,no codes or nothing else happens?So any suggestions on this...
Thanks in advance,
Tony

http://www.corvettebuyers.com/c4vettes/ecm.htm

Cliff Harris

Try the info on this page instead (the methodology changed over the years):

http://corvettephotographs.com/c4vettes/codes.htm

tony58

Thanks Cliff ,that worked fine....

Good news is that it worked.Bad news is the codes that came up.C12 which is normal.Then the dreaded H16.Also H 26 came up.
Bought the car in Aug.2014 had new Opti,water pump,belt,hoses and other new parts.Car always starts and runs like a new one.
Only problems I've had is a battery drain.I have to keep a tender on it or it drains in about a week.Small oil drip,that I was going to address this Winter...
Does 16 always mean a new OPTI?
Thanks all in advance.
Tony

tony58

I've been doing some searching and reading old post.Is it good news that the codes that came up are H not C? So the H means its not anything to worry about now?It had a new OPTI. installed before I bought it in Aug..so it would be in history.So I should take the neg.battery connect off and see if it comes back?
Trying to find out whats going on before it goes to a mechanic...
Thanks in advance

Cliff Harris

Resetting the ECM to clear the codes is always a good idea to make sure they are old and no longer applicable.