Siemens Simatic S7-400

LED
BAF
LED
BATT1F
LED
BATT2F
Cause of fault Remedy
H H D Battery 1 empty or missing
No external backup voltage
available (short-circuit or over‐
load)
Insert new battery in compartment 1.
Press FMR button.
● Fault after plugging in a module:
Plugged-in module defective
● Fault after switching on: Remove
all modules and plug in
individually
D H D Battery 1 empty or missing Insert new batteries in compart‐
ments 1 and 2 Press FMR button.
Battery has been stored for too
long
External backup voltage avail‐
able
Depassivate battery (see Installation
Manual ).
H D H Battery 2 empty or missing
No external backup voltage
available (short-circuit or over‐
load)
Insert new battery in compartment 2.
Press FMR button.
● Fault after plugging in a module:
Plugged-in module defective
● Fault after switching on: Remove
all modules and plug in
individually
D D H Battery 2 empty or missing Insert new batteries in compart‐
ments 1 and 2 Press FMR button.
Battery has been stored for too
long
External backup voltage avail‐
able
Depassivate battery (see Installation
Manual ).
H D D Both batteries in order.
No external backup voltage
available (short-circuit)
● Fault after plugging in a module:
Plugged-in module defective
● Fault after switching on: Remove
all modules and plug in
individually
D D D Both batteries in order.
External backup voltage avail‐
able
-
D = LED is dark; H = LED lights up;
Power supply modules
3.5 Fault/Error messages via LEDs
S7-400 Automation System Module Data
Reference Manual, Ausgabe 11/2016, A5E00850736-08 53