0392344 JOHNSON SWITCH & KEY ASSEMBLY, Ignition

Table 1
Diagnostic Codes Table
Code Conditions which Generate this Code System Response
338-5 Engine Pre-Lube Pump Relay : Current Below Normal While the output driver is off for five seconds, the Electronic Control Module (ECM) detects an open in the circuit for the prelube pump's solenoid for more than five seconds. The code is logged.
The alarm output is activated.
338-6 Engine Pre-Lube Pump Relay : Current Above Normal While the output driver is on for five seconds, the ECM detects a short in the circuit for the prelube pump's solenoid for more than five seconds. The code is logged.
The alarm output is activated.
339-5 Engine Pre-Lube Pressure Switch : Current Below Normal The prelube pump pressure switch is OPEN. The oil pressure that is measured from the engine oil pressure sensor is greater than 50 kPa (7.25 psi). The ECM normally monitors the prelube pump pressure switch. In this case, the engine oil pressure sensor will be monitored. This determines if the prelube pump is supplying oil to the engine.
The alarm output is activated. The code is logged. The output to the prelube relay remains energized until the engine control switch is turned to the STOP position. The ECM contains the logic and the outputs that control the engine's prelubrication, start-up, and shutdown. The logic for starting and for stopping is customer programmable. The logic responds to inputs from the following components: engine control switch, emergency stop switch, remote start switch, data link and other inputs.The prelube pump will not operate if the emergency stop button is activated or if the engine speed is greater than 0 rpm.When the conditions permit operation and the logic determines that lubrication is required, the ECM provides +Battery voltage to the prelube pump's solenoid. After activation, the prelube pump will operate until one of the following occurrences:
The programmable "Prelube Time" expires.
The emergency stop button is pressed.The ECM monitors the prelube pump pressure switch in order to verify lubrication of the engine prior to start-up. The pressure switch is normally open.Before start-up, the pressure switch closes when the prelube pump raises the engine oil pressure to 9 3 kPa (1.3 0.4 psi). After the pressure switch closes, the prelube pump operates for the programmable "Prelube Time". The engine starting sequence continues.If the ECM does not detect closure of the pressure switch within the time that is designated in the parameter "Prelube Time Out", an "E233 Low Engine Prelube Pressure" event code is generated. The "Prelube Time Out" is configurable. If the prelubrication does not occur, the starting sequence is terminated.At shutdown, the pressure switch opens when the engine oil pressure is reduced to 9 3 kPa (1.3 0.4 psi).The prelube pump can also be operated with a manual switch. When the switch is closed, a +Battery signal is sent to the ECM. The ECM provides +Battery voltage to the prelube pump's solenoid until the switch is released or until the prelubrication pressure switch closes.The prelubrication system also operates after shutdown. This ensures that the turbocharger has adequate lubrication during engine shutdown. When the engine reaches 0 rpm, the output for the prelube pump will operate for three minutes.Note: On some engines, the flash file allows the time interval to be programmed for a longer period of time.When +Battery voltage is supplied to the prelube pump's solenoid, the ECM also provides +Battery voltage to the "Prelube Active" indicator in the control panel (if equipped).Before you troubleshoot the prelubrication system, make sure that the ECM is programmed properly. The "Prelube Time Out" must be programmed to a value between 30 and 300 seconds. Make sure that the hardware is installed: prelube pump, solenoid for the pump, prelubrication pressure switch and manual prelube switch. Make sure that the wiring is installed. Refer to the engine's electrical Schematic.Logged diagnostics provide a historical record. Before you begin this procedure, use Caterpillar Electronic Technician (ET) to print the logged codes to a file.The most likely causes of the diagnostic code are a poor electrical connection or a problem in a wiring harness. The next likely cause is a problem with the prelube pump's solenoid. The least likely cause is a problem with the ECM.The troubleshooting procedure may generate additional diagnostic codes. Keep your mind on correcting the cause of the original diagnostic code. Clear the diagnostic codes after the problem is resolved.
Illustration 1 g01436333
Schematic of the circuit for the prelube pump on the in-line engines and the vee engines
Test Step 1. Inspect the Electrical Connectors and Wiring
Illustration 2 g01431198
Terminal Box
(1) ECM connector J2/P2
(2) ECM connector J1/P1
(3) 16 amp circuit breaker
(4) Connectors J3/P3 for the customer's connector
(5) Connectors J4/P4 for the optional control panel (if equipped) or for a customer's connector
(6) J5/P5 connectors for the harness
(7) J6/P6 connectors for the harness
Turn the engine control switch to the OFF/RESET position. Switch the 16 amp circuit breaker for the ECM OFF. Switch the 6 amp circuit breaker OFF. Note: For the following steps, refer to Troubleshooting, "Electrical Connectors - Inspect".
Illustration 3 g01436339
Inside of the control panel (if equipped)
(8) "Manual Prelube" switch and "Prelube Active" indicator
(9) Terminal strip
Illustration 4 g01436341
P2 ECM terminals that are used by the circuit for the prelube pump on in-line engines and vee engines
(P2-12) Circuit driver for the prelube pump's solenoid
(P2-22) Return
Illustration 5 g01436344
Terminal locations at the P5 connector on the terminal box that are for the prelube pump's solenoid and prelube pump pressure switch on the in-line engines
(P5-12) Return
(P5-13) Circuit driver for the prelube pump's solenoid
(P5-69) Digital return
(P5-70) Prelube pump pressure switch