210 Auto. Trans. Equipped Models

With engine coolant temperature below 122°F (50°C), start engine and adjust engine speed to approximately 1600 RPM with transmission in "P" Check ignition timing.
From inside vehicle, connect a jumper wire between test connector terminals. See Fig 1. Recheck ignition timing. System is functioning properly if timing does not change with jumper wire installed. If timing changes, check for a defective thermal vacuum switch.
NOTE: System damage will occur if Jumper wire is connected between any other terminals.

Fig 1: Connecting Jumper Wire To Test Connector (210 With Auto. Trans.)
Courtesy of NISSAN NORTH AMERICA, INC.
Allow engine to reach normal operating temperature, then recheck ignition timing with jumper wire still installed. System is functioning properly if timing has advanced. If timing does not advance, test individual system components to locate cause.
To complete system testing, check top gear detecting switch. With engine idling, disconnect lead wires from vacuum switching valve at connectors. Apply parking and service brakes and block drive wheels.
NOTE: Vacuum switching valve wires MUST be disconnected during step 5) or damage to ohmmeter will result
Using an ohmmeter, check continuity between test connector terminals with transmission in "R" and then again with transmission in "N". See Fig 1.
Top gear detecting switch is okay if ohmmeter shows continuity with transmission in "R" and no continuity with transmission in "N". If not, replace top gear detecting switch.