Joined: Mar 2008

Posts: 2,088

Likes: 2

From: South Side Chicago

Year: 1992, 2- 1998 (All 3, 4 Doors)

Model: Cherokee

Engine: 4.0L in all

Test the MAP Sensor output voltage at the MAP Sensor connector terminal B (as marked on the sensor body). This is done with the ignition switch ON and the engine OFF. Output voltage should be 4-5 volts.

Test engine controller (terminal 5) for the same voltage as described above to verify the wire harness condition. Repair as necessary.

Test MAP Sensor supply voltage at sensor connector (terminal C) with the ignition ON. The voltage should be approximately 5V (+/- 0.5V). 5V (+/- 0.5V) should also be at terminal 6 of the engine controller wire harness connector.

Test the MAP Sensor ground circuit at the sensor connector (terminal A) and the engine controller connector (terminal 4).

Test the MAP Sensor ground circuit at the engine controller connector between terminal 4 and terminal 11 with an ohmmeter. If the ohmmeter indicates an open circuit, inspect for a defective sensor ground connection. This connection is located on the right side of the cylinder block, at the oil dipstick tube mounting stud. If the ground connection is good, replace the engine controller. If terminal 4 has a short circuit to 12V, correct this condition before replacing the engine controller.