Checking the GAZ-3110 switch

The transistor switch type 131.3734 or 90.3734 is installed on the car on the left mudguard behind the battery

It converts the control pulses of the Hall sensor in the ignition distributor into current pulses in the primary winding of the ignition coil.

Since the switch generates a large amount of heat during operation, it is necessary to periodically clean the switch case from dirt and dust and do not cover it with foreign objects.

Removing the Switch

Disconnect the negative terminal from the battery.

Removing the Switch

Having marked the position of the wires on the switch, unscrew the three screws with a screwdriver.

Removing the Switch

Using a 10 key, unscrew the two nuts securing the switch and remove it.

Having installed the switch in place, we check the correct connection of the wires according to the diagram.

Switch test

Checking the GAZ-3110 switch

Switch test diagram

  • 1 – ammeter;
  • 2 - battery;
  • 3 - switch;
  • 4 - switch;
  • 5 - high voltage wire;
  • 6 - ignition coil


  • 1. Remove the switch from the car by unscrewing the two fastening nuts and disconnecting the wires.
  • 2. Assemble the circuit shown in the figure on a suitable metal plate.

Fix the tip of high voltage wire 5 at a distance of 6–7 mm from the plate.

When switch 4 is turned on, ammeter 1 should show a current within 6-7 A, and after 1-3 seconds, the current should drop to 0.

At the moment the switch 4 is turned off, a spark should jump between the tip of the high voltage wire 5 and the plate (permanent sparking is possible).

Otherwise switch 3 is defective and must be replaced.