Cub Cadet SLTX1000 Series - Manual (Page 35)

Electronic Power Steering
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13. Check the current draw of the EPS assembly.
13a. Leave the DMM connected to the ground wire
on the EPS and the battery.
13b. Place an amp clamp meter on the red wire with
a black trace. See Figure 3B.9.
NOTE: Cut the tape that seals the loom at the EPS con-
nector end of the harness and slide the loom off of
the wires to attach the amp clamp.
13c. Start the tractor.
NOTE: The voltage reading on the DMM should now read
over 13 volts. If it does not, repair the charging cir-
cuit before proceeding with troubleshooting the
EPS system.
13d. Without sitting on the tractor, turn the steering
wheel a quarter turn back and forth. Watching
the voltage reading on the DMM and the current
reading on the amp clamp while doing this.
NOTE: If the voltage drops below 13 volts and the current draw does not rise above 15 amps, repair the circuit
suppling voltage to the EPS before proceeding with troubleshooting the EPS system.
NOTE: If the voltage drops below 13 volts and current draw is more than 15 amps, the problem is inside the
EPS assembly and it must be replaced.
13e. Turn off the tractor.
14.Remove the DMM and the amp clamp meter.
15.Check the input from the ignition module.
15a. Connect the ground lead of an oscilloscope to a
good ground on the engine block.
15b. Back probe the EPS harness connector at the
yellow wire with a white trace using the positive
(+) lead of the oscilloscope.
15c. Start the engine.
16. The oscilloscope should show a pulsed signal. The
bottom or resting phase of each pulse must be below
5 volts. The peak of each pulse must be over 5 volts.
See Figure 3B.10.
17. The pulses must be at 9 Hertz (cycles/second) or
higher (engine needs to be >490 RPM).
18. If the resting phase of the pulse is above 5 volts,
there is a short in the safety circuit of the tractor that
is pulling up the voltage of the ignition module.
Figure 3B.9
Red wire
with black trace
Figure 3B.10
5 volt
reticle