424531 Volvo.Penta Nozzle

Table 1
Diagnostic Codes Table
Code and Description Conditions which Generate this Code System Response
298-2 Service Brake Pedal Switch erratic, intermittent, or incorrect Both contacts of the switch for the right brake pedal are in the same state. The code is logged. The ECM will disable the automatic control of engine speed through the throttle lock feature . The "Throttle Lock with Throttle Backup" allows the operator to maintain a desired engine speed without the use of the throttle pedal.The throttle lock feature uses three switches and the right brake pedal for inputs to the engine ECM:Throttle Lock Switch - This is a rocker switch that is used to enable the throttle lock feature. No diagnostics are performed on this switch input.Right Brake Pedal - The right brake pedal switch is a double-pole single-throw switch. The switch is used to disengage the engine speed from the throttle lock's engine speed setpoint while the throttle lock feature is being used. When the right brake pedal is used to disengage the engine speed from the setpoint, the setpoint is stored in ECM memory. The engine speed can be reset to the setpoint by the operator's use of the resume switch. Two switch inputs are used to monitor the status of the right brake pedal. One input is normally open while the other input is normally closed. Diagnostic codes are available for the right brake pedal switch.Set/Decel Switch - The Set/Decel switch can be used to establish the setpoint for the throttle lock feature. The switch can also be used to lower a setpoint that has already been established. The Set/Decel switch can be depressed in order to establish the setpoint for the throttle lock feature. The throttle pedal is used to establish the desired engine speed. The setpoint for the throttle lock may be viewed on the service tool status screen. When a setpoint is established, the operator may depress the Set/Decel switch in order to decrease the engine speed. When the switch is bumped, the engine speed will decrease by 20 rpm. Hold the switch in order to decrease the engine speed at a rate of 50 rpm per second. The operator may use the throttle pedal to increase the engine speed beyond the set point. No diagnostics are performed on this switch input.Resume/Accel Switch - The Resume/Accel switch can be used to resume a previous set point. The Resume/Accel switch can also be used to increase an already established set point. If the right brake pedal has been used to disengage the engine speed from the setpoint for the throttle lock, the operator may press the Resume/Accel switch in order to resume the previous setpoint. The right brake pedal must be released in order to resume the setpoint. The previous set point will only exist if the right brake pedal or the engine retarder has been used to disengage throttle lock. When the resume switch is pressed, the desired engine speed will accelerate to the previous set point at a rate of 2000 rpm per second. The previous setpoint is cleared from memory if the throttle lock switch has been turned to the OFF position, or if the ECM has been powered down. Once a set point is established, the operator may depress the Resume/Accel switch in order to increase the engine speed by 20 rpm. The switch can be held in order to increase the engine speed at a rate of 50 rpm per second. No diagnostics are performed on this input.The throttle lock feature also provides a throttle backup. If the throttle sensor fails, the engine speed will default to low idle. While the throttle lock feature is enabled, the Set/Decel switch and the Resume/Accel switch can be used to fully control the engine speed.If a diagnostic code for the right brake pedal becomes active, the throttle lock feature will be disabled. The power must be cycled in order to enable the throttle lock feature. The engine will still respond to the throttle pedal.
Illustration 1 g01342126
Schematic for the throttle lock feature
Test Step 1. INSPECT ELECTRICAL CONNECTORS AND WIRING
Turn the keyswitch to the OFF position.
Illustration 2 g01343069
Locations of the ECM connectors for the throttle lock feature
(1) J1/P1 ECM connectors
(2) Machine interface connectors (25-Pin)
(3) Machine interface connectors (20-Pin)
Illustration 3 g01343057
Locations of the components in the cab of the machine for the throttle lock feature
(4) Right brake pedal
(5) Throttle pedal
(6) Throttle lock switch
(7) Set/decel switch
(8) Resume/accel switch
Thoroughly inspect ECM connectors (1), machine connectors 2 and 3, the switch for right brake pedal (4), the sensor for throttle pedal (5), the throttle lock switch (6), the Set/Decel switch (7), and the Resume/Accel switch (8). Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 4 g01342635
Terminal locations at the P1 ECM connector for the throttle lock switch
(P1-5) Digital return
(P1-35) Set/decel switch
(P1-41) Throttle lock's on/off switch
(P1-44) Right brake pedal switch (N/O)
(P1-45) Right brake pedal switch (N/C)
(P1-59) Resume/accel switch
Illustration 5 g01343071
Terminal locations at the machine interface connector (25-Pin)
(Terminal 2) Throttle lock's Set/Decel switch
(Terminal 3) Throttle lock's Resume/Accel switch
(Terminal 5) Throttle lock switch (on/off)
Illustration 6 g01343072
Terminal locations at the machine interface connector (20-Pin)
(Terminal 10) Right brake pedal switch (N/C)
(Terminal 11) Right brake pedal switch (N/O)
(Terminal 12) Digital return
Illustration 7 g01342639
Terminal locations at the throttle lock's on/off switch
(Terminal 2) Digital return
(Terminal 3) Throttle