Peterbilt 387 – Warning Alarms
See also: Peterbilt PDF manuals & wiring diagrams
A warning alarm indicates that some condition in the vehicle requires attention. A warning alarm can be indicated in the following ways:
- Red warning LEDs in the 2-inch gauges
- Vehicle safety warning messages in the SMC
- System fault warning messages in the SMC
A warning alarm will continue until the condition that caused it is corrected. At that time, the SMC will display a Reset message for 10 seconds, and the warning indications will cease. Pressing the Reset switch clears the Reset message sooner.
Vehicle Safety Warning Messages
Messages advising of unsafe operating conditions can appear in the SMC. Examples are a major engine or transmission problem (low oil pressure, high tempera- ture, low coolant level) and a problem with the brake safety (low air pressure). An audible alarm will accompany these warning messages.
Vehicle safety warning messages are listed in Table 2-2 on page 2-6. Column 1 shows the warning message as it appears in the SMC, and column 2 identifies its meaning. Column 3 identifies the gauge whose red warning LED lights. Column 4 shows the associated Reset message.
You can temporarily override vehicle safety warning messages two ways:
- Press the Reset switch for 3 seconds. This will dismiss the message and silence the buzzer. If an active alarm still exists, the message and buzzer will return.
- Press the Reset switch for 1 second, then press the Select switch to display any other function. The warning message will disappear for 60 seconds. It will then reappear and remain until the condition causing it is corrected. The audible alarm will continue to sound.
System Fault Messages
A system fault message indicates a problem exists with the Model 387 Instrument System that does not directly affect vehicle safety. These occur when the ignition is first switched on. The messages are:
IM CAL, IM CFG, IM DIAG, IM LIN, IM SLFT, ODO ERR, NO DATA, SMC MEM.
System fault messages are detected by the Interface Module or the SMC. No gauge LED is associated with them, no audible warning will sound, and no Reset message will appear.
The NO DATA message can occur any time, not just during System Initialization.
|Gauge||Indication When Led Is On||Activating Condition|
|Air Cleaner Restriction||Clogged||More than 25“ of water (H2O)|
|Air Tank 1||Too low||Less than 66 psi|
|Air Tank 2||Too low||Less than 66 psi|
|Air Starter Air Pressure||No indication||Not activated|
|Ammeter||Incorrect discharge rate||>25 amps when RPM <1200, or
>2 amps when RPM >1200
|Auxiliary Transmission Oil Temp||Too high||Higher than 230° F|
|Brake Saver Application Air Pressure||No indication||Not activated|
|Brake Saver Oil Temp||Too high||Higher than 230° F|
|Center Drive Axle Oil Temp||Too high||Higher than 230° F|
|Engine Load||No indication||Not activated|
|Engine Oil Pressure||Too low||Engine ECU|
|Engine Oil Temperature||Too high||Engine ECU|
|Front Drive Axle Oil Temp||Too high||Higher than 230° F|
|Fuel Filter Restriction||Clogged||More than 7“ of mercury|
|Fuel Level (left, right, or main tank)||Low fuel||18 tank or less|
|Fuel Pressure||No indication||Not activated|
|Load Gauge Air Pressure||No indication||Not activated|
|Main Transmission Oil Temp||Too high||Programmable|
|Manifold Boost||No indication||Not activated|
|Pusher Suspension Air Pressure||No indication||Not activated|
|Pyrometer||Too high||Higher than 1200° F|
|Tractor Brake Applic. Air Pressure||No indication||Not activated|
|Rear Drive Axle Oil Temp||Too high||Higher than 230° F|
|Tag Suspension Air Pressure||No indication||Not activated|
|Trailer Brake Applic. Air Pressure||No indication||Not activated|
|Voltmeter||Too low or too high||>15 volts or <10 volts|
|Engine Coolant Temp||Too high||Engine ECU|
|6X6 Front Drive Axle Oil Temp||Too high||Higher than 230° F|
|Air Deflector Position||No indication||Not activated|
|Transfer Case Oil Temp||Too high||Higher than 230° F|
|Warning Message||Condition||Associated Gauge LED||Reset Message|
|H2O TMP||Coolant temperature high||Water Temperature||H2OT OK|
|LOW AIR1||Air tank #1 pressure low||Primary Air Pressure||AIR1 OK|
|LOW AIR2||Air tank #2 pressure low||Secondary Air Pressure||AIR2 OK|
|OILPRES||Engine oil pressure low||Engine Oil Pressure||OIL OK|
|OIL TEMP||Engine oil temperature high||Engine Oil Temperature||OILT OK|
|TRANTMP||Main transmission oil
|Main Transmission Oil Temperature||TRAN OK|
|CAUTION! If a message that is not listed in this table appears, do not ignore it. The vehicle should be serviced regardless of the message that appears.|