JLG 510AJ Service Manual - Manual (Page 190)

SECTION 3 - CHASSIS AND TURNTABLE
3-148 – JLG Lift – 3121181
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 posi-
tion information from the throttle actuator and is not.
• Corrective Action(s)- Illuminate MIL, sound audible warn-
ing or illuminate secondary warning lamp. Shutdown
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 inter-
rupted, the ECM can no longer control the position of the
throttle.
This fault will set if the key is on, the throttle actuator is receiv-
ing power, and the ECM is not receiving digital information
from the actuator.
Diagnostic Aids
• Verify that the throttle actuator 5V supply voltage is pres-
ent at the actuator.
• Check for a all four TPS feedback wires for short circuits.
• Check TPS SER+ and TPS SER- wire routing with respect to
noise sources (ignition coils, spark plug coil wires, etc.) and
shield if necessary.
2
16
13
12
1
5V_ext
Vs=+5 VDC
5V_rtn
TPS1
TPS SER +
+
-
Motor
DBW-
DBW+
ECM
H-Bridge
19
TPS SER -
Serial
xmitter
Electronic Throttle Actuator w/Analog Position Feedback Electronic Throttle Actuator w/Serial Position Feedback