JLG 460SJ Service Manual - Manual (Page 257)

SECTION 3 - CHASSIS & TURNTABLE
3120895 – JLG Lift – 3-205
DTC 1652- TPS1 Loss of Communications
• Throttle Actuator (with serial/digital position feedback)
• Check Condition- Key On, Engine Running and/or
Stopped
• Fault Condition- ECM is expecting to receive throttle
position information from the throttle actuator and is
not.
• Corrective Action(s)- Illuminate MIL, sound audible
warning or illuminate secondary warning lamp. Shut-
down engine.
• Non-emissions related fault
In the case of a throttle actuator with serial/digital position
feedback, the ECM receives a constant data stream from
the throttle actuator. If the communication is absent or
interrupted, the ECM can no longer control the position of
the throttle.
This fault will set if the key is on, the throttle actuator is
receiving power, and the ECM is not receiving digital infor-
mation from the actuator.
Diagnostic Aids
• Verify that the throttle actuator 5V supply voltage is
present at the actuator.
• Check for a all four TPS feedback wires for short cir-
cuits.
• Check TPS SER+ and TPS SER- wire routing with
respect to noise sources (ignition coils, spark plug coil
wires, etc.) and shield if necessary.