AC DRIVE SPEED CONTROLLER ERROR CODES

The Curtis 1238 AC controllerprovides diagnostic information to assist in the troubleshooting of drivesystem problems in a similar fashion as the DC controller.  The diagnostic information can be obtained byobserving the appropriate display on the handheld programmer or the fault codesissued by the 2 Status LEDs.  The pair ofLEDs built into the controller (one red, one yellow) produce flash codesdisplaying all the currently set faults in a repeating cycle.  Each code consists of two digits.  The red LED flashes once to indicate that thefirst digit of the code will follow; the yellow LED then flashes theappropriate number of times for the first digit.  The red LED flashes twice to indicate thatthe second digit of the code will follow; the yellow LED flashes the appropriatenumber of the times for the second digit. An example of the code for “Battery Under-Voltage” (code 23) is shown inthe following flash sequence diagram.

The LEDs have 4 different displaysmodes that indicate the type of information they are providing.  These types are summarized in Table 6 below.

The following troubleshooting chart(Table 7) provides the following information on all the controller faultsincluding the ways to identify each fault, possible causes, and the “set” and“clear” conditions associated with each. Whenever a fault is encountered and no wiring or vehicle fault can befound, shut off the key switch and turn it back on to see if the faultclears.  If not, shut off the key switchand remove the 35-pin connector to the controller.  Check for connector corrosion or damage,clean it if necessary, and re-insert it.