Ok, I wrote to ZAPI and they replied:

Hello
It means:

KO => inverse OK => not working = not right = not OK

Example
VACC not OK = Minus and Max are different to saved in memory.
Pedal wire KO = connection between controller and throttle has been broken.

Best regards.
Jorge Ferrari

I think KO means the opposite of OK.

The fact that it had to be discussed on a forum shows it is a very poor choice of abreviation.

none taken ;o)

apparently zapi are the only guys that use this abbreviation in their error codes and nowhere to they actually explain what the acronym really stands for so it's anyones guess ;o)

No offence.
Checked it, but I couldn't find it in the Zapi manuals at FSIP. I bet you're right KO might mean Key On with certain charts. All I know that with Zapi it means Knock Out.

Pedal wire KO = Open circuit in the accelerator wiring
Can Bus KO = No signals from the can bus
Thermic Sensor KO = implausible signal from tremal sensor
etc.

yes if your dealing with hvac standards KO may mean Knock Out, which may be referring to a knockout in an electrical box maybe.

but in error code charts they always refer to the circuit condition when the error occurs and they will show it as consistant with Key On or KO when they describe the error code in its definition.

go to fsip's website and go through the zapi error codes and you will see what i mean.

;o)

agree with my netherlands friend

KO = Knock Out

i believe the correct engineering term for 'KO' is 'Key On'

usually somewhere in service manuals they show abbreviation chart showing what all the acronyms mean, USUALLY... but not always.

STEER SENSOR KO
This is an alarm which signals an out of range of the steering potentiometer signal. The
fault condition is entered in these two following conditions:
- the "Set steer 0 pos" (straight wheels programmation) parameter is wrong (lower
than "Set steer min" or higher than "Set steer max").
- the feedback signal of the steering potentiometer is outside the window defined by
"Set steer min" and "Set steer max" parameters.
In the first case, repeat the steering potentiometer acquisition. In the second case,
check the steering poti and its wiring. Eventually, repeat again the steering
potentiometer acquisition.
SLAVE KO
Slave and Master µCs perform a cross-check in order to verify their functionality. If the
MASTER detects SLAVE µC malfunctioning, it brings the controller in a safe status
opening the power bridge and the Line Contactor.
EEPROM KO
Fault in the area of memory in which the adjustment parameters are stored; this alarm
does not inhibits truck operation, but the controller will use default parameters. If the
defect persists when the key is switched OFF and ON again, replace the logic. If the
alarm disappears, remember that the parameters stored previously have been cancelled
and replaced by the default values.

Thaneth b

I. Remember when the Mk 1 MR reach trucks came out and on courses l attended circuit diagrams were in Italian and fault codes and explanations often explanations ended in KO. We took the explanation KO to be knocked out as in boxing.

Nero