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Chevy expert, ASE Certified Technician
Category: Chevy
Satisfied Customers: 10370
Experience:  30 yrs experience ase cetified tech shop owner
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88 corvette: service engine light comes on but the only code..ECM.

Customer Question

I have a 88 corvette that the service engine light comes on but the only code that I get is 12 that tells me that it is ready to show problem codes. I clear the light but it keeps coming back on. Could I have a bad ECM. Thanks in advance for any advice for any advise you can give me.
Submitted: 5 years ago.
Category: Chevy
Expert:  Chevy expert replied 5 years ago.
Welcome to just I'm here to help you and your 100% satisfaction is my goal.Yes if the only code that you're coming up with is a code 12 And the service engine soon light is on there's one of two things that can cause this either a faulty or defective EC M or a faulty defective ignition control module , it will also show a code 12 when there's a lack of distributor reference signal
Customer: replied 5 years ago.
What is a distributor refrence signal?
Expert:  Chevy expert replied 5 years ago.
If the EC M is not seeing the RPM reference signal It can also set a code 12 using a scan tool see if you have an RPM signal registering at the EC M