DTC Advanced Diagnostics: U0151
DTC U0151:Lost Communication With SRS Unit

General Description
Without CAN gateway

With CAN gateway (12P connector type)

With CAN gateway (16P connector type)

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 transmission control module (TCM) 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, Shift position indicator blinks

Enable Conditions
Condition
Minimum
Maximum
12 volt battery voltage [Battery Voltage]
10.0 V
–
[ ]: HDS Parameter

Malfunction Threshold
One of these conditions is met:
The TCM does not receive any signals from the SRS unit via 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.
F-CAN circuit F-CAN_H line open*1
F-CAN circuit F-CAN_L line open*1
F-CAN circuit F-CAN A_H line open*2
F-CAN circuit F-CAN A_L line open*2
F-CAN circuit F-CAN_H line short to ground*1
F-CAN circuit F-CAN_L line short to ground*1
F-CAN circuit F-CAN A_H line short to ground*2
F-CAN circuit F-CAN A_L line short to ground*2
F-CAN circuit F-CAN B_H line open*2
F-CAN circuit F-CAN B_L line open*2
F-CAN circuit F-CAN B_H line short to ground*2
F-CAN circuit F-CAN B_L line short to ground*2
SRS unit failure (include fuse fall-outs)
TCM internal circuit failure

*1: Without CAN gateway
*2: With CAN gateway

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the shift position indicator blinks and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the TCM memory. The MIL does not come on.

Conditions for clearing the DTC
The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.