POWER TAKE-OFF (PTO)
Peterbilt Motors Company 8-15
PTO AND PUMP MODE WARNING
Instrument panel wiring:
Pump mode warning lamp is an editable telltale and requires a diode.
PTO engaged warning lamp Peterbilt is an editable telltale and requires a diode.
The diodes prevent relay coil back feed from driving the CECU input high which could activate the warning lamp
(bi-stable input) giving false indications.
CK_K10 spare relay #3 is used to power the PTO hour meter whenever the PTO engaged warning lamp is on.
ENGINE WIRING
The ISX engine controller port (J2 pin 94) will report a PTO active when driven low (grounded). When a PTO is specified
on a chassis the ISX engine harness will contain the optional remote throttle/PTO 12-way connector and cap
(P111A/J111A).
The MX engine controller port (J2 pin 21) will report a PTO active when driven high (+12V DC). Since PTO and pump
mode signals are low (grounded) when active, a relay is needed to convert the low (ground) signal to a high (+12V DC)
signal. This relay is installed below the left hand side of the cab near the chassis node. When a PTO is specified on a
chassis the MX engine harness will contain the optional remote throttle/PTO 12-way connector and cap (P111C/J111C).
The remote throttle/PTO 12-way connector is located on the back, left hand side of the engine as shown in Detail “A” of
Figure 8-20. See Figure 8-24 for pin out information of the 12-way connector. There are also 16-way and 23-way
connectors available for setting up dual station controls or other high content applications. See Figure 8-25 for the 16-way
pin out information and Figure 8-26 for the 23-way pin out information. The CECU parameters for REMOTE PTO
CONTROL and REMOTE THROTTLE CONTROL may need to be enabled.
There are two common methods of utilizing remote engine speed controls:
1) A 5V variable signal can be used to control the engine speed via a potentiometer. For this configuration the
CECU parameter for REMOTE THROTTLE may need to be activated.
-For the MX engine, pins 3, 4 and 10 can be connected to the potentiometer to convert the 5V signal to a remote
throttle signal.
-For Cummins engines, pins 4, 10 and 11 can be used the same way as described above for the MX engine.
2) The engine speed can be bumped up or down using momentary switches or preset speeds. For this configuration
the CECU parameter for REMOTE PTO may need to be activated.
-For the MX engine, momentarily connecting pin 8 to pin 2 will increase the engine speed. Momentarily
connecting pin 8 to pin 1 will decrease the engine speed.
-For Cummins engines, the engine will go to the first set speed when PTO mode is initially activated by applying
ground from pin 3 to PTO ON/OFF pin 5. If this connection is broken and reapplied within 0.5 seconds, the
engine will go to set speed 2. If this is done again, the engine will go to set speed 3 and so on. There are up to 5
preset speeds that can be modified using INSITE. If the connection is broken longer than 0.5 seconds and then
reapplied, the engine will go back to set speed 1.
