HOSE AS 2434788 - Caterpillar

FMI F01
This code is recorded when ESTC II reads the electrical system voltage at contact A1 as below normal range (less than 15 V for one second).The transmission does not shift as a result of this fault condition. Voltage is too low to energize the shift solenoids.The possible causes of this code are:
A charging system component has failed.
The harness wiring has failed.
ESTC II has failed.STEP 1. CHECK BATTERY VOLTAGE - Measure the voltage at the battery posts.
Voltage is less than 15 DCV. The charging system is not correct. Check the charging system. See module Service Manual, SENR2947, "Starting and Charging System".
Voltage is 15 DCV or greater. This should not cause ESTC II failure. Go to Step 2.STEP 2. CHECK SYSTEM VOLTAGE AT ESTC II- Disconnect the machine harness from ESTC II. Turn the disconnect and key start switches to the ON position. At machine harness connector "A" for ESTC II measure the voltage between contact 1 and contact 2.
Voltage is less than 15 DCV. The machine harness has failed. Check the +battery and ground circuits of the machine harness. Repair or replace the machine harness.
Voltage is 15 DCV or greater. This should not cause the ESTC II failure. Inspect connector "A". Connect the machine harness to ESTC II. If the CID 168 FMI F01 code remains present (fault present indicator is ON), replace ESTC II. See the topic ESTC II Replacement.