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Convertible Top Relay 1988 Cavalier Z24?

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Can anyone tell me if there is a convertible top relay on a 1988 Cavalier Z24? If so, where is it located? If not, why would it not be operating if the motor was tested good (used replacement) and the fuse is good. Also motor was said to be receiving power by the GM dealer who put my top back up manually. They said old motor was bad but had power. I put in new motor and still nothing.

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  • From what you are saying, there must be a relay hiding somewhere. Did you try tracing the wires?

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  • Hi there.

    The wiring does not list a relay in the circuit. According to the wiring the windows will not operate if there is a relay. If the windows are working it does not have a relay.

    Did you bench test the new motor? If the new motor is good, then the issue could be:

    •         wiring
    •         switch
    •         circuit breaker
    •         bad ground
    •         fuse

    You mention the fuse is good. There are some additional fuse checks that can be made in case you haven't already. Sometimes if a fuse has been taken out and put back in several times the connection can be degraded. To make sure the fuse is good take it out and make sure it has a good connection inside and that you have current. Sometimes fuses look ok but they can be blown on the side where you can't see it.

    Aftermarket relays are available so one could have been added to your Z24. If there is a relay the only thing you can do is follow the wires from the switch and the motor through the circuit to the wires at the relays under the hood at the firewall. Try and match the wire colors. Use caution!

    If needed, check your ChiltonDIY subscription for basic circuit breaker and fuse testing as well as basic electrical troubleshooting for your Z24. It is in the Chassis Electrical section under "Circuit Protection" and "Understanding and Troubleshooting Electrical Systems."


  • Thanks for the help... here is what I have found.

    I have power at the switch and can I can also power the motor manually, bypassing the switch. All works great. There are 3 wires going into the switch are colored PINK (Constant power), Purple (powers top down), Gray (powers top up). There isn't any ground wires coming into the switch.

    The power uses what I am told a reverse polarity. If you jump the Pink and Purple and ground the Gray, the top goes down. If you jump the Pink and Gray and ground the Purple, the top goes up. Again though, the switch doesn't have a ground supplied so its only purpose is to jump the wires.

    QUESTION - Where is the ground supplied to reverse the polarity?!

  • Sounds like you might have a bad switch! Usually the motor is grounded at the mounting position. The switch changes the polarity positions. Or there could be a wiring problem from the switch to the motor.

    1. Disconnect the connector from back of control switch. Set the transaxle in Park or Neutral position and turn the ignition ON. Using a test light, check for voltage at the center terminal. If no voltage is present, check the power window circuit breaker. If the breaker is okay, check the wiring for a short or open.

    2. If there is voltage at the center terminal of the connector, connect a 12-gauge jumper wire between the center terminal and either terminal on the connector. Repeat with the remaining terminal and the center terminal. If the motor operates with the jumper wire but not with the switch, replace the switch.

    3. If the switch tests okay, reconnect the wiring. Disconnect the Purple wire from the motor in the trunk. Connect a test light to the Purple wire and ground. Activate the switch in the down position. If light does not come on the wire is open or shorted.

    4. Repeat the test with the Gray wire but activate the switch in the up position. If the tester does not light up, check the motor-to-body ground connection. If the ground is okay, check for an open or short in the Gray wire.

  • I have a question. Was there a difference in the motors made from '83-'88 and '89-'92? I purchased a used motor from an '89 and found out that they possibly used a relay to ground the motor. '83-'88 did not use a relay (Found this out after going over everything on my car). The motor from the '89 is only working when I add ground the switch to reverse the polarity.

    My switch is good so I know it isn't that. The '89 motor is also good and so is all the wiring in the cars harness. One thing I did notice is the '89 motor did not come with an external ground wire. But I assumed since it was used it wasn't sent. I took it from my old one and added it. Could this be why it isn't grounding properly? The '89 motor might not be accepting of the external ground and required the relay??

  • From what you are saying, there must be a relay hiding somewhere. Did you try tracing the wires?