If a malfunction in the power source circuit occurs, or a malfunction in communication with the skid control module, or in a speed sensor occurs, the 4WD control module will prohibit operations by the fail safe function.
This diagnostic procedure supports the following DTC:
DTC C1241 Low Power Supply Voltage
This DTC shall run when the ignition is On.
When one of the following conditions is met:
| • | For 10 seconds or more, at a vehicle speed of 3 km/h (2 mph) or more, voltage of the 4WD control module terminal 11 is 9.5 volts or less. | 
| • | When both of the following continue for 60 seconds or more: | 
| - | With the voltage of the 4WD control module terminal 11 is 9.5 volts or less and communication with the skid control module cannot be performed. | 
| - | A malfunction in communication with the skid control module. | 
| • | For 3 seconds or more, with the voltage of the 4WD control module terminal 11 is 9.5 volts or more, communication with the skid control module cannot be performed. | 
The 4WD control module will prohibit operations by the fail safe function.
The DTC will clear when conditions for setting the DTC have been repaired.
Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
Schematic Reference: Transfer Case Control Schematics Connector End View Reference: Component Connector End Views  | ||||
1  | Did you perform the Diagnostic System Check - Vehicle?  | --  | Go to Step 2  | |
2  | 
 Is any DTC set?  | --  | Go to Step 3  | |
3  | 
 Is the resistance measured within the specified value?  | Below 1 Ohms  | Go to Step 4  | Go to Step 8  | 
4  | 
 Is the voltage measured within the specified values?  | 10-14 Volts  | Go to Step 5  | Go to Step 7  | 
5  | Measure the voltage between the 4WD control module connector IG1 terminal 23 and body ground. Is the resistance measured within the specified values?  | Below 1 Ohm  | Go to Step 6  | Go to Step 7  | 
6  | 
 Is any DTC set?  | --  | Go to Step 9  | Go to Step 10  | 
7  | Repair or replace harness or 4WD control module connector. Did you complete the repair or replacement?  | --  | Go to Step 10  | --  | 
8  | Replace fuse IG1. Did you complete the replacement?  | --  | Go to Step 10  | --  | 
9  | Replace 4WD control module. Did you complete the replacement?  | --  | Go to Step 10  | --  | 
10  | 
 Does the DTC reset?  | --  | Go to Step 2  | System OK  |