Good afternoon everyone,
I am new to both Corvette (1991 convertible Auto) ownership and the forum so I would like to say hello. This is the first GM vehicle I have owned in a long time but the C4 has always been on my list of cars to own. I have loved the lines since I was very young and am happy to add it to my small collection of vehicles. I bought the car about three weeks ago with some known electrical issues but the price was way too good to pass up. I bought the FSM and received it yesterday!

On to my situation. I don't know where to start. The car runs fine but, the cooling fans do not come on. I have reviewed the forums and now the FSM for trouble shooting and the trouble shooting requires the use of a Tech 1 and turning the A/C on. But the A/C does not work ,there is no power to the control panel and I have not bought the Tech 1. (is there an alternative to the Tech 1? I would hate to spend $700 on a 30 year old piece of electronics) I have done the basic trouble shooting checking for power and so on and the fans come on when the relay is jumped both relays are fine and I changed out the temp sensor (located under the throttle body) and still nothing. I reviewed the FSM and see that the ground for the sensor is shared with the TPS but I cannot seem to locate it in the engine compartment. Do you think it could be this?

Now for the A/C. I troubleshot this one on before I received the manual. No power to the C68 Control panel, no power to the A/C fuse on the side of the dash. The FSM shows another A/C fuse in the engine compartment by the blower but I have not been able to locate that one to check it. I used a 12v lead from the battery to what should have been the "hot" side of the A/C fuse and the control panel came on and I was able to adjust the blower motor. (engine was off so I did not check for A/C clutch engagement). From what I can see the A/C is powered from fusible link K that should be on the starter, but it is not. It might be worth noting the previous owner installed a push button starter for some reason. I guess my question is where does the fusible link K actually go? I need to be able to rewire it in but don't know where to trace it back to. I cannot seem to find that info in the FSM.

Thanks in advance for your assistance!
Shannon

 

Did you get the electrical book?
it is separate.
the cooling fans come on when the ECM turns them on.
the car puts 12 volts out there, and the ECM Puts out the grounds to complete the circuit.
there are no grounds at the top of the engine.
The engine is the ground for the sensors!! Frame grounds bolt to the engine.
they are at the left side of the bellhousing near the oil temp sender above the oil filter.
i would guess you have to dig into the harness at the back of the right valve cover to find the wire that needs the fusible link.
you can crimp and solder the wire.
i would not trust just one splice method.
you might just see if the previous owner mistook that wire for the solenoid ign. Wire.
the fusible wire is red and the solenoid wire is purple.
you know GM uses the battery lead + to go directly to the starter solenoid. And they use that point to add circuits.
there are other battery terminals behind the battery.