HUB 1137228 - Caterpillar

Illustration 1 g01954286There are two types of outputs. There are driver outputs and sinking outputs. The driver outputs include the PTO Outputs, Starter Interlock Output and the Backup Alarm. These outputs are capable of driving 2 Amps of current at battery voltage.The sinking outputs include the Converter Indicator output. This driver is capable of 0.3 Amps.If the replacement of a relay or a solenoid is larger than the original, meaning that the replacement has a higher amperage capability, then the ECU output may disable in order to keep from destroying the internal parts of the ECU components. A diagnostic code will not be generated in this type of situation. The output will appear not to function.Perform the following check:
Turn the ignition switch OFF. Disconnect the replacement relay or solenoid. Instal a test lamp. Turn the ignition switch ON and activate the output. If the test lamp indicates that the output is functional, the replacement relay or solenoid must be replaced with a relay or solenoid that meets the origninal specifications. If it is necessary, a smaller relay or solenoid can be used in order to operate the larger relay or solenoid.There are four types of outputs that are rated for driving relays or solenoids. These outputs are rated at 2 amps at the chassis battery voltage.
Table 1
2 Amp Output Drivers
Name Pin Location
PTO #1 Enable Output J2-2
Backup Alarm Output J2-5
PTO #2 Enable Output J2-6
Starter Interlock Output J2-7 There are six additional low power drivers that are capable of 300 milliamps.
Table 2
300 mA Output Drivers
Name Pin Location
Engine Governor Output J2-11
Shifter #1 Active Indicator J2-12
Shifter #2 Active Indicator J2-13
Transmission Output Speed Driver J2-19
Torque Converter Output Speed Driver J2-20
Torque Converter Indicator J2-21 Note: Replacing a driver with one that is rated for a higher amperage may result in loss of functions. If a loss of a function results after replacing a driver or relay, ensure that the replaced driver or relay is properly rated.