Erratic Signal Test
- Ignition OFF, remove the MAP sensor.
- Install a 3A fused jumper wire between the 5-volt reference circuit terminal C and the corresponding terminal of the MAP sensor.
- Install a jumper wire between the low reference circuit terminal A of the MAP sensor and ground.
- Install a jumper wire at terminal 3 of the MAP sensor.
- Connect a DMM between the jumper wire from terminal B of the MAP sensor and ground.
- Ignition ON, with the J 23738-A
or J 35555
, slowly apply vacuum to the sensor while observing the voltage on the DMM. See Special Tools
. The voltage should vary between 0-5.2 volts, without any spikes or dropouts.
- If the voltage reading is erratic, replace the MAP sensor.