Throttle Switch Circuit - Test - Perkins 1104E Series Troubleshooting Manual

212
Troubleshooting Section
E. Repeat this procedure for each of the following
ECM pin connections:
•
P1:11 Set speed control continue or accelerate
•
P1:19 Set speed control speed 1 or speed 2
•
P1:20 Set speed control or decelerate
•
P1:28 Set speed control ON or OFF
•
P1:29 Set speed control clutch or brake
disengage
Expected Result:
The status screen should display an OPEN condition
with the switch in the OFF position.
The status screen should display a CLOSED
condition with the switch in the ON position.
Results:
•
OK – The ECM is working correctly. STOP.
•
Not OK – The ECM is not working properly.
Repair: Temporarily connect a test ECM.
The test ECM should be programmed with the
correct software. All parameters should be set to
the same values as the suspect ECM.
If the problem is eliminated with the test ECM,
reconnect the suspect ECM.
If the problem returns with the suspect ECM, then
the suspect ECM is faulty.
Replace the suspect ECM.
Verify that the repair has eliminated the problem.
STOP.

Throttle Switch Circuit - Test

System Operation Description:
Use this procedure under the following circumstances:
•
Throttle switch inputs can be switched to ground.
•
Verification of the throttle switch
Also, use this procedure if another procedure has
directed you here.
The throttle switch provides the operator with the
ability to select the desired engine speed. Engine
speed will decrease with increasing load. The throttle
switch is a rotary switch with ten positions.
The throttle switch is connected to the four throttle
inputs of the Electronic Control Module (ECM). Each
position generates a specific on/off pattern on the
throttle inputs. A diagnostic code is generated if a
pattern that does not correspond with any of the
switch positions is detected.
Once a diagnostic code is generated, the ECM
ignores the throttle input signals and desired engine
speed is set to the last valid pattern that was
recognized by the ECM. Desired engine speed is set
to low idle while the engine is not running.
Voltage at the throttle inputs to the ECM should be
11.5 ± 0.5 VDC when the throttle inputs are open.
The voltage should be less than 0.5 VDC when the
throttle inputs are closed.
i01798878
RENR2696-01