C4 Diagnostic Trouble Codes

Codes, Codes, Codes…

Have you noticed “SYS” intermittently showing up in your 1990-1996 Corvette’s speedometer display?  This means there is a trouble code stored in one of the on-board control modules.  When the 1990 Corvette debuted, GM introduced ECM (Engine Control Module) and CCM (Central Control Module) trouble codes.   In addition, ABS/ASR (Anti-lock Brake System/Acceleration Slip Regulation) and EBTCM (Electronic Brake Traction Control Module) trouble codes and data were introduced on the 1992-1996 Corvettes.  Although limited ECM data is available, it can point you in the right direction.  For example, the CCM interaction is invaluable when diagnosing interior component or courtesy light problems and the VATS (Vehicle Anti-theft System).  The ALDL (Assembly Line Diagnostic Link) is used to access the codes with a jumper wire.  The jumper wire is placed in the proper connector slots and the interrogation begins.  Interrogation can be a daunting task. (more…)

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1956-1962 Windshield Wiper Transmissions

By Joe Calcagno (www.rarecorvettes.com)

There’s an old saying: “You never miss the water until the well runs dry.” This is true. In a
manner of speaking the windshield wipers on a car are the same. That is, you never think
about them until you need them, and if they won’t work, you usually don’t have time for a
repair. As a result, as soon as the rain is over, you go on with all the other things in life,
never again thinking about the wipers until the next time it rains. Then it’s the same all over
again.

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Corvette C6 Battery Concerns

The C6 Corvette is a true World Class performance car with excellent “daily driver” attributes. Everywhere you look on the C6, an electronic device is operating something we had to either manually perform or think about previously. All of these electronic gadgets require stable voltage for long life. The days of removing the battery cable to see if the charging system is working are long gone. The C6 Corvette battery has to maintain all of the electronic requirements while effortlessly starting the car. In light of this, we typically have very little thought about servicing or checking the battery. They sit there without attention until we have difficulty starting our car.

(more…)

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