Ambient Air Pressure Sensor Circuit
|
Overview
CODE | REASON | EFFECT |
Fault Code: 222 PID: P108 SPN: 108 FMI: 4 LAMP: Yellow SRT: 00-095 |
Low voltage detected at the ambient air pressure sensor signal pin 27 of the sensor harness connector. | Engine power output derated by 15 percent. |
Ambient Air Pressure Sensor Circuit |
Circuit Description
The ambient air pressure sensor monitors atmospheric pressure and passes information to the electronic control module (ECM) through the sensor harness.
Component Location
- M11 – The ambient air pressure sensor is located on the engine block above the fuel supply pump.
- 1994 N14 – The ambient air pressure sensor is located on the engine block to the right of the ECM.
- 1991 N14 – The ambient air pressure sensor is located on the engine block to the left of the ECM.
Shop Talk
Monitor the ambient air pressure reading with a service tool to confirm that the pressure reading matches the actual air pressure.
For active Fault Code 222 after a recalibration, verify an ambient air pressure sensor is part of the Control Parts List (CPL). If not, recalibrate with “a calibration without save and restore” that does not require an ambient air pressure sensor, or install an ambient air pressure sensor.
Cautions and Warnings
CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
CAUTION
To reduce the possibility of pin and harness damage, use the breakout cable to perform this test procedure: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use this breakout cable when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
Troubleshooting Steps
STEPS | SPECIFICATIONS | |
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STEP 1. | Check for multiple fault codes. | |
STEP 1A. Read the fault codes. | Fault Codes 123, 141, 145, 154, 213, 352, and 422 are not active | |
STEP 2. | Check the ambient air pressure sensor. | |
STEP 2A. Inspect the ambient air pressure sensor and sensor harness connector pins. | No damaged pins | |
STEP 2B. Read the fault codes. | Fault Code 222 active | |
STEP 2C. Check the ECM ambient air pressure sensor supply voltage. | 4.75 to 5.25 VDC | |
STEP 2C-1. Check the ambient air pressure sensor supply voltage. | ||
STEP 2C-2. Measure the voltage out of the ECM. | ||
STEP 2D. Check the ECM ambient air pressure signal voltage. | 0 m [0 ft] (sea level) – 4.00 to 4.58 VDC, 914.4 m [3000 ft] – 3.60 to 4.40 VDC, 1828.8 m [6000 ft] – 3.20 to 4.00 VDC, 2743.2 m [9000 ft] – 3.00 to 3.80 VDC , 3567.6 m [12,000 ft] – 2.60 to 3.40 VDC | |
STEP 2D-1. Check for a short circuit from pin to pin. | ||
STEP 2D-2. Check for continuity in the sensor harness. | ||
STEP 2D-3. Check ECM response. | ||
STEP 2D-4. Check ECM pin resistance. | ||
STEP 3. | Check the sensor harness. | |
STEP 3A. Inspect the sensor harness and the ECM connector for damaged pins. | No damaged pins | |
STEP 3B. Read the fault codes. | Fault Code 222 active | |
STEP 3C. Check for a short circuit to ground. | More than 100k ohms | |
STEP 3D. Check for a short circuit from pin to pin. | More than 100k ohms | |
STEP 4. | Check for the ECM response. | |
STEP 4A. Check for the appropriate ECM response. | Fault Code 222 inactive, Fault Code 221 active | |
STEP 4B. Check ECM signal pin resistance. | Less than 100k ohms | |
STEP 5. | Clear the fault codes. | |
STEP 5A. Disable the fault code. | Fault Code 222 inactive | |
STEP 5B. Clear the inactive fault codes. | All fault codes cleared |
Guided Step 1 – Check for multiple fault codes.
Guided Step 1A – Read the fault codes. | |
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Conditions
Action
|
|
OK | NOT OK |
Fault Codes 123, 141, 145, 154, 213, 352, and 422 are not active | Possible sensor failure, short circuit to ground in the sensor 5 VDC common supply, or short circuit from pin to pin. |
Fault Code Multiple A
|
|
Guided Step 2 – Check the ambient air pressure sensor.
Guided Step 2A – Inspect the ambient air pressure sensor and sensor harness connector pins. | |
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Conditions
Action
|
|
OK | NOT OK |
No damaged pins | Repair the damaged pins.
|
Guided Step 2B – Read the fault codes. | |
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Conditions
Action
|
|
OK | NOT OK |
Fault Code 222 active | Repair complete. |
CAUTION
To reduce the possibility of pin and harness damage, use the breakout cable to perform this test procedure: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 2C – Check the ECM ambient air pressure sensor supply voltage. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
4.75 to 5.25 VDC | Does not meet specifications. | |
CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement: |
Guided Step 2C-1 – Check the ambient air pressure sensor supply voltage. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
4.75 to 5.25 VDC
|
Does not meet specifications. | |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 2C-2 – Measure the voltage out of the ECM. | ||
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Conditions
Action
|
|
|
OK | NOT OK | |
4.75 to 5.25 VDC | Replace the ECM. Refer to Procedure 019-031. | |
CAUTION
To reduce the possibility of pin and harness damage, use this breakout cable when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 2D – Check the ECM ambient air pressure signal voltage. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
0 m [0 ft] (sea level) – 4.00 to 4.58 VDC, 914.4 m [3000 ft] – 3.60 to 4.40 VDC, 1828.8 m [6000 ft] – 3.20 to 4.00 VDC, 2743.2 m [9000 ft] – 3.00 to 3.80 VDC , 3567.6 m [12,000 ft] – 2.60 to 3.40 VDC | Does not meet specifications. | |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
Guided Step 2D-1 – Check for a short circuit from pin to pin. | |
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Conditions
Action
|
|
OK | NOT OK |
More than 100k ohms | Repair or replace the sensor harness. |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
Guided Step 2D-2 – Check for continuity in the sensor harness. | |
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Conditions
Action
|
|
OK | NOT OK |
Less than 10 ohms | Correct pin-to-pin wiring or open circuit. |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 2D-3 – Check ECM response. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
Fault Code 222 inactive, Fault Code 221 active | Fault Code 122 active
|
|
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 2D-4 – Check ECM pin resistance. | |
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Conditions
Action
|
|
OK | NOT OK |
Less than 100k ohms
|
Greater than 100k ohms
|
Guided Step 3 – Check the sensor harness.
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 3A – Inspect the sensor harness and the ECM connector for damaged pins. | |
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Conditions
Action
|
|
OK | NOT OK |
No damaged pins | Repair the damaged pins |
Guided Step 3B – Read the fault codes. | |
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Conditions
Action
|
|
OK | NOT OK |
Fault Code 222 active | Repair complete. |
CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement: |
Guided Step 3C – Check for a short circuit to ground. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
More than 100k ohms | Repair or replace the sensor harness. | |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
Guided Step 3D – Check for a short circuit from pin to pin. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
More than 100k ohms | Repair or replace the sensor harness. | |
Guided Step 4 – Check for the ECM response.
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 4A – Check for the appropriate ECM response. | ||
---|---|---|
Conditions
Action
|
|
|
OK | NOT OK | |
Fault Code 222 inactive, Fault Code 221 active | Replace the ECM. Refer to Procedure 019-031. | |
CAUTION
To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
Guided Step 4B – Check ECM signal pin resistance. | |
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Conditions
Action
|
|
OK | NOT OK |
Less than 100k ohms | Replace the ECM. Refer to Procedure 019-031. |
Guided Step 5 – Clear the fault codes.
Guided Step 5A – Disable the fault code. | |
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Conditions
Action
|
|
OK | NOT OK |
Fault Code 222 inactive | Return to troubleshooting steps or contact your nearest Cummins Authorized Repair Location if all the steps have been completed and checked again. |
Guided Step 5B – Clear the inactive fault codes. | |
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Conditions
Action
|
|
OK | NOT OK |
All fault codes cleared | Troubleshoot any remaining active fault codes. |
Repair complete
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Appropriate troubleshooting charts
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