DTC U0151 (L15B7/L15BA/L15BY: Without CAN gateway (PGM-FI System))

DTC U0151:  F-CAN Malfunction (Powertrain Control Module (PCM)-SRS Unit)

General Description 

Courtesy of HONDA, U.S.A., INC.

The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (F-CAN_H and F-CAN_L). When the information is not sent from the SRS unit via the F-CAN lines and this condition continues for a specified time or when the information sent from the SRS unit is abnormal and this condition continues for a specified cycle, the powertrain control module (PCM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution	Continuous
Sequence	None
Duration	1.5 seconds or more
DTC Type	One drive cycle, MIL off

Enable Conditions 

Condition	Minimum	Maximum
Elapsed time after the vehicle condition is turned to the ON mode	3 seconds	-
12 volt battery voltage [BATTERY]	10.0 V	-

[ ]: HDS Parameter

Malfunction Threshold 

One of these conditions is met:

• The PCM does not receive any signals via the F-CAN lines for at least 1.5 seconds.
• The information sent from the SRS unit is abnormal at least 20 times.

Possible Cause 

NOTE:  The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

• SRS unit failure (include fuse fall-outs)
• F-CAN circuit F-CAN_H line open
• F-CAN circuit F-CAN_L line open
• F-CAN circuit F-CAN_H line short to ground
• F-CAN circuit F-CAN_L line short to ground
• PCM internal circuit failure

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected, a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC 

The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.