SEAL-RING 8T3540 - Caterpillar

System Operation Description:Use this procedure to determine if the circuit for the exhaust brake (output 3) is operating correctly. There are no diagnostic codes for this output.Background InformationThe circuit for the exhaust brake relay is controlled by the Engine Control Module (ECM). The output indicates that conditions are acceptable for an exhaust brake to operate. Operation of the exhaust brake is inhibited during undesirable engine operating conditions. When the cruise control on/off switch is in the OFF position, the following conditions exist:All of the following conditions must be met in order to ensure the proper operation of the exhaust brake:
Engine speed is above 1000 rpm.
The accelerator pedal position is less than seven percent.
The clutch pedal is released.
The switch for the exhaust brake is on.
The PTO on/off switch is off.When the cruise control on/off switch is in the ON position, the following conditions exist:"Engine Brake Mode" ParameterWhen the cruise control on/off switch is on, this parameter provides two special options that allow the exhaust brake to be operated only after the driver has depressed the service brake pedal. The two modes of operation that follow are customer programmable:
The coast mode engages the exhaust brake when the driver depresses the service brake pedal. The exhaust brake disengages when the driver releases the service brake pedal.
The latch mode engages the exhaust brake when the driver depresses the service brake pedal. The exhaust brake remains engaged until the control detects a change in the control input. The following actions are examples of a change in a control input:
The throttle is depressed.
The clutch pedal is depressed.
The engine speed drops below 900 rpm.The third option for the "Engine Brake Mode " parameter is "Manual". The manual mode operates in the same manner regardless of the position of the cruise control on/off switch. The driver is not required to depress the service brake pedal in order to initiate the exhaust brake. Depress the service brake pedal in order to initiate the exhaust brake in the latch mode and in the coast mode.Note: The latch mode and the coast mode are customer programmable options. The latch mode and the coast mode determine the operation of the exhaust brake only when the cruise control switch is in the ON position. The latch mode and the coast mode do not determine the operation of the exhaust brake when the engine is active in cruise control. Latch mode and coast mode require the initiation of the service brake before acting. The action of the service brake disengages the cruise control.Note: The output for the exhaust brake is disabled whenever the PTO on/off circuit is on and the customer parameter "PTO Configuration" is programmed to "Cab Switches", to "Remote Switches", or to "Remote Throttle".Warm Up ModeThe exhaust brake can be used to apply a parasitic load to the engine in order to aid engine warm-up. The exhaust brake will help the engine achieve normal operating temperatures. To use this feature, the parameter "Exhaust Brake Warm Up Configuration" must be programmed