How To Test The MAP Sensor (1996, 1997, 1998, 1999 2.5L OHV Dodge Dakota)

The MAP sensor, on the 1996, 1997, 1998, and 1999 2.5L OHV Dodge Dakota, can be easily tested with a multimeter and a vacuum pump.

In this tutorial, I'll show you how to bench test the manifold absolute pressure (MAP) sensor so that you can find out if it's defective or not.

With your test results, you'll be able to diagnose the following MAP sensor trouble codes P0107 and P0108.

Contents of this tutorial:

  1. Symptoms Of A Bad MAP Sensor.
  2. OBD II Trouble Code P0107 And P0108.
  3. MAP Sensor Circuit Descriptions.
  4. TEST 1: Testing The MAP Sensor Voltage Signal.
  5. TEST 2: Verifying MAP Sensor Has 5 Volts And Ground.
  6. MAP Sensor Trouble Code Doesn't Go Away.
  7. Where To Buy The MAP Sensor And Save.
  8. More 2.5L Dodge Dakota Tutorials.

NOTE: The test for the 1994-1995 2.5L SOHC Dodge Dakota can be found here: How To Test The MAP Sensor (1994-1995 2.5L SOHC Dodge Dakota).

Symptoms Of A Bad MAP Sensor

Your Dodge Dakota uses 3 inputs to calculate how much air the engine is breathing. These are intake manifold pressure, intake air temperature and engine RPM. These inputs are provided, respectively, by the MAP sensor, the intake air temp (IAT) sensor, and the crankshaft position sensor.

Since the MAP sensor is a mission-critical component of the engine management system, when it fails, your Dodge Dakota is gonna' feel it.

Here are some specific symptoms you'll see when the manifold absolute pressure (MAP) sensor fails:

  1. The check engine light is lit with one of the following trouble codes:
    1. P0107: MAP Sensor Voltage Too Low.
    2. P0108: MAP Sensor Voltage Too High.
  2. Engine is difficult to start.
  3. Rough engine idle.
  4. Black smoke coming out if the tail pipe when engine is running.
  5. Lack of power when accelerating the engine or vehicle down the road.

OBD II Trouble Code P0107 And P0108

When the manifold absolute pressure (MAP) sensor fails on your 1997-2003 2.5L Dodge Dakota, you're gonna' see one of two trouble codes lighting up the check engine. These are:

  1. P0107: MAP Sensor Voltage Too Low
  2. P0108: MAP Sensor Voltage Too High.

Knowing what causes each trouble code to pop up will help you troubleshoot and resolve the MAP sensor trouble code. With this in mind, here's a brief explanation of what these troubles mean for your Dodge Dakota.

Trouble Code P0107: MAP Sensor Voltage Too Low: This trouble code is telling you that your Dodge Dakota's fuel injection computer is seeing a MAP sensor voltage lower than a predetermined voltage (in its program) when the engine starts.

Trouble code P0107 usually sets when the MAP sensor fails and reports a voltage that is between 2.3 to 0.2 Volts DC with the KEY ON ENGINE OFF (instead of a voltage of about 4.5 Volts) or a voltage of 0.2 Volts DC with the KEY ON ENGINE RUNNING for a period of about 2 seconds.

Trouble Code P0108: MAP Sensor Voltage Too High: This trouble code is telling you that your Dodge Dakota's fuel injection computer is seeing a MAP sensor voltage greater than a predetermined voltage (in its program) when the engine starts and runs.

Trouble code P0108 usually sets when the MAP sensor fails and reports a voltage that is at or above 4.5 Volts DC with the KEY ON ENGINE RUNNING longer than 2 seconds.

The P0108 trouble code can also be set when the insulation on the MAP sensor wires starts to fall off and the wires short to each other. This causes the fuel injection computer to see the 5 volts from the MAP sensor's power feed on the MAP signal wire.

MAP Sensor Circuit Descriptions

The MAP sensor is 3 wire type sensor. This means that it has a power wire, a ground wire and a signal wire. The table below has a brief description of each:


MAP Sensor Circuits 1997-1999 2.5L Dodge Dakota
Terminal Wire Description
1 BLK/LT BLU Ground
2 DK GRN/RED MAP Signal
3 VIO/WHT 5 Volts DC

Let's turn the page and get testing...