Signal Too Low. Permanent Fault
Signal too low. Permanent fault
EFI-422 Atmospheric pressure sensor, signal
Checking power cable
- Ignition off.
- Disconnect atmospheric pressure sensor.
- Ignition on.
Connect a voltmeter between atmospheric pressure sensor connector terminal 1 and ground.
The voltmeter should read 5 V.
OK - Checking signal cable resistance
Not OK - Checking power cable resistance to ground
-------------------------------------------------
Checking signal cable resistance
- Ignition off.
- Wait for approximately 150 seconds (cars with immobilizer 245 seconds).
- Atmospheric pressure sensor disconnected.
Connect an ohmmeter between atmospheric pressure sensor connector 3 and ground.
The ohmmeter reading should be higher than 0.2 Mohms.
OK - Checking atmospheric pressure sensor
Not OK - Checking for a short-circuit
-------------------------------------------------
Checking for a short-circuit
- Check the cable between atmospheric pressure sensor terminal 3 and engine control module (ECM) #B22 for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Checking atmospheric pressure sensor
- Ignition off.
- Connect atmospheric pressure sensor.
- Start the engine and idle it.
- Use the Volvo Scan Tool (ST) to read off the value OF the atmospheric pressure sensor signal.
This value should be approximately 4.5 V at sea level and normal atmospheric pressure.
OK - Checking for contact resistance and oxidation
Not OK - Replacing component
-------------------------------------------------
Checking for contact resistance and oxidation
The cause of the diagnostic trouble code (DTC) has been loose connections in the atmospheric pressure sensor connector.
- Check connector for contact resistance and oxidation and remedy according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Replacing component
- Try a new atmospheric pressure sensor.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Checking power cable resistance to ground
- Ignition off.
- Atmospheric pressure sensor disconnected.
- Wait for approximately 150 seconds (cars with immobilizer 245 seconds).
Connect an ohmmeter between atmospheric pressure sensor connector 1 and ground.
The ohmmeter should read approximately 0.2 - 1.5 kohms.
OK - No Fault Found
Low - Checking accelerometer
High - Checking control module connector
-------------------------------------------------
Checking accelerometer
- Ignition off.
- Atmospheric pressure sensor disconnected.
- Disconnect accelerometer.
Connect an ohmmeter between atmospheric pressure sensor connector 1 and ground.
The ohmmeter should read approximately 0.2 - 1.5 kohms.
OK - Replacing component
Not OK - Fault-tracing information
-------------------------------------------------
Fault-tracing information
- 1. the car has leak diagnostic.
- 2. the car does not have leak diagnostic.
Select a suitable alternative.
1 - Checking fuel tank pressure sensor
Not OK - Checking for a short-circuit
-------------------------------------------------
Replacing component
- Try a new accelerometer.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Checking fuel tank pressure sensor
- Ignition off.
- Atmospheric pressure sensor disconnected.
- Accelerometer disconnected.
- Disconnect fuel tank pressure sensor.
Connect an ohmmeter between atmospheric pressure sensor connector 1 and ground.
The ohmmeter should read approximately 0.2 - 1.5 kohms.
OK - Replacing component
Not OK - Checking the air conditioning (A/C) pressure sensor
-------------------------------------------------
Replacing component
- Try a new fuel tank pressure sensor.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Checking the air conditioning (A/C) pressure sensor
- Ignition off.
- Atmospheric pressure sensor, fuel tank pressure sensor and accelerometer disconnected
- Disconnect the air conditioning (A/C) pressure sensor.
- Ignition on.
Connect ohmmeter between atmospheric pressure sensor terminal 1 and ground.
The ohmmeter should read approximately 0.2 - 1.5 kohms.
OK - Replacing component
Not OK - Checking for a short-circuit
-------------------------------------------------
Replacing component
- Try a new air conditioning (A/C) pressure sensor.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Checking for a short-circuit
The atmospheric pressure sensor power cable is connected inside the engine control module (ECM) to the air conditioning (A/C) pressure sensor, fuel tank pressure sensor and accelerometer power cables.
If anything happens to any of these cables all four will be affected.
Check cables between:
- Air conditioning (A/C) pressure sensor terminal 3 and engine control module (ECM) #B29.
- Tank pressure sensor terminal 1 and engine control module (ECM) #B15.
- Accelerometer terminal 1 and engine control module (ECM) #B1.
- atmospheric pressure sensor terminal 1 and engine control module (ECM) #B29
- for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Select "Continue" when the check has been made.
Continue - Verification
-------------------------------------------------
Checking control module connector
- Ignition off.
- Atmospheric pressure sensor disconnected.
- Check control module connector for contact resistance and oxidation and remedy according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
- Control module connected.
Connect an ohmmeter between atmospheric pressure sensor connector 1 and ground.
The ohmmeter should read approximately 0.2 - 1.5 kohms.
OK - Fault-tracing information
Not OK - Checking for an open-circuit
-------------------------------------------------
Fault-tracing information
- The cause of the diagnostic trouble code (DTC) has been loose connections in the control module connector.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Checking for an open-circuit
- Check cable between atmospheric pressure sensor terminal 31 and engine control module (ECM) #B29 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Select "Continue" when the fault has been repaired.
Continue - Verification
-------------------------------------------------
Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied as follows:
- Ignition off.
- Reconnect connectors and reinstall components.
- Start the engine and idle it.
- Wait for a minute.
- Select Volvo Scan Tool (ST) to read off diagnostic trouble codes (DTCs).
If EFI-422 is stored it should have intermittent status.
OK - VERIFIED
Not OK - VERIFICATION FAILED
------------------------
VERIFIED - FAULT FOUND
VERIFICATION FAILED - Fault-tracing information
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.
Do you want to exit fault-tracing?
Yes - Exit fault-tracing
No - Attempt New Test
------------------------
Attempt New Test - Checking power cable
-------------------------------------------------