Z31 Fuse and Relay Information
Your basic electrical circuit consists of an electrical component and its associated switches, motors, relays and such as well as the necessary wires and connectors to connect the component to the battery and the chassis. If you plan on troubleshooting any electrical circuit, locate a copy of the wiring diagram appropriate to what you're working on and examine it carefully—you may be able to eliminate certain potential causes of your problem if certain components on that circuit are functioning properly.
If several components or circuits fail simultaneously, your problem could be related to a fuse or a ground connection, since there can be multiple circuits routed to the same fuses and grounds.
Component failure can often be caused by simple electrical problems, such as a loose or corroded connection, blown fuses, or melted fusible links. Always check the condition of wires, connectors, and fuses before tearing everything apart!
If all else fails, break out the testing equipment. Have a circuit tester or voltmeter, a continuity tester, and a jumper wire handy to bypass electrical components. Check wiring diagrams before attempting to use any test equipment to determine the necessary connection points for troubleshooting.
Testing Your Circuit
- Voltage Test: Connect one lead of your circuit tester to a known good ground and the other to a connector in the malfunctioning circuit, as close as possible to the battery or nearest fuse. If you are getting voltage here, that part of the circuit is good—continue testing further along. If you find a point with no voltage, the problem lies between there and your last good test point. Some circuits only show voltage when the ignition is in the Accessory or On position.
- Checking for Shorts: Remove the corresponding fuse and connect a test light in its place. Jiggle the wiring harness. If the light comes on, there's a short to ground somewhere—possibly where some insulation is eroded.
- Ground Testing: If a component may not be grounded, disconnect the battery. Use a continuity tester between a known good ground and the wire or ground in question. If the bulb lights, the ground is good. If not, the ground is bad.
- Continuity Test: Disconnect the battery. Connect the tester leads to opposite ends of the circuit. If the bulb lights, electricity is flowing correctly.
Relay & Fuses
Various electrical circuits have relays to keep heavy loads off sensitive contact points. Relays are located in various places in the car.
Below is a diagram found on the Engine Compartment Relay block cover. Most Z31 cars have this missing or unreadable:
Nissan Part Number for Above Sticker:
24137-Z31002Fuses
All electronics are protected by a combination of fuses and fusible links. The fuse box is located in the driver's side lower kick panel—each fuse location is listed on the inside cover (see image below). The fusible links are located under the hood on the passenger side near the battery. If a link is melted, the link must be replaced.
Nissan Part Numbers for Above Sticker:
- 1984-1985 - All Models (24313-Z31001)
- 1986 All Models (24313-Z31002)
- 1987-1989 All Models (24313-Z31003)
Sources Used
- 1984-1988 Nissan 300ZX Factory Service Manual
- Writen by: XenonZcar