DTC Troubleshooting: P0102
DTC P0102: MAF Sensor Circuit Low Voltage
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
Confirmed DTC
Pending DTC
P0102 MAF Sensor Circuit Low Voltage
   

1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the ON mode, and wait 2 seconds.

?2.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
MAF SENSOR
Less than 0.1
V
    

Do the current condition(s) match the threshold?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at MAF sensor/IAT sensor 1 and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot.?
2.
Fuse check:

Fuse check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Check the following fuse.
Fuse
No. B21 (10 A)
Location
Under-dash fuse/relay box

Is the fuse OK?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
Repair a short in the IG1 ACG/IG1(AFM) wire between MAF sensor/IAT sensor 1 and the No. B21 (10 A) fuse. Also replace the No. B21 (10 A) fuse.?
3.
Open wire check (IG1 ACG/IG1(AFM) line):

Open wire check (IG1 ACG/IG1(AFM) line)
?1.
Disconnect the following connector.
MAF sensor/IAT sensor 1 5P connector

?2.
Turn the vehicle to the ON mode.

?3.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
MAF sensor/IAT sensor 1 5P connector: disconnected
Test point 1
MAF sensor/IAT sensor 1 5P connector (female terminals) No. 3:
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The IG1 ACG/IG1(AFM) wire is OK. Go to step 4.
     
NO
     
     
     
Repair an open in the IG1 ACG/IG1(AFM) wire between MAF sensor/IAT sensor 1 and the No. B21 (10 A) fuse in the under-dash fuse/relay box.?
4.
Determine possible failure area (VGP line, others):

Determine possible failure area (VGP line, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Measure the resistance between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
MAF sensor/IAT sensor 1 5P connector: disconnected
Test point 1
MAF sensor/IAT sensor 1 5P connector (female terminals) No. 5:
Test point 2
Body ground


Is there 190?210 k??

     
YES
     
     
     
Go to step 7.
     
NO
     
     
     
Go to step 5.
5.
Shorted wire check (VGP line):

Shorted wire check (VGP line)
?1.
Jump the SCS line with the HDS, and wait more than 1 minute.


?2.
Disconnect the following connector.
PCM connector E (80P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
MAF sensor/IAT sensor 1 5P connector: disconnected
 
PCM connector E (80P): disconnected
Test point 1
MAF sensor/IAT sensor 1 5P connector (female terminals) No. 5:
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
Repair a short in the VGP wire between the PCM (E61) and MAF sensor/IAT sensor 1.?
     
NO
     
     
     
The VGP wire is not shorted. Go to step 6.
6.
Open wire check (VGP line):

Open wire check (VGP line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
MAF sensor/IAT sensor 1 5P connector: disconnected
 
PCM connector E (80P): disconnected
Test point 1
MAF sensor/IAT sensor 1 5P connector (female terminals) No. 5:
Test point 2
PCM connector E (80P) No. 61


Is there continuity?

     
YES
     
     
     
The VGP wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P0102 goes away and the PCM was substituted, replace the original PCM.?
     
NO
     
     
     
Repair an open in the VGP wire between the PCM (E61) and MAF sensor/IAT sensor 1.?
7.
MAF sensor/IAT sensor 1 check (substitution):

MAF sensor/IAT sensor 1 check (substitution)
?1.
Substitute a known-good MAF sensor/IAT sensor 1.

?2.
Reconnect all connectors.

?3.
Turn the vehicle to the ON mode.

?4.
Clear the DTC with the HDS.


?5.
Start the engine.

?6.
Hold the engine speed at 2,000 rpm without load (CVT in P or N, M/T in neutral).

?7.
Check for Pending or Confirmed DTCs with the HDS.
DTC Description
Confirmed DTC
Pending DTC
P0102 MAF Sensor Circuit Low Voltage
   

Is DTC P0102 indicated?

     
YES
     
     
     
MAF sensor/IAT sensor 1 is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P0102 goes away and the PCM was substituted, replace the original PCM.?
     
NO