5005996 JOHNSON Service Manual - English

Table 1
Diagnostic Codes Table
Description Conditions which Generate this Code System Response
E043(1) Low System Voltage The battery voltage to the ECM is less than normal. The code is logged.
168-0 System Voltage HIgh The battery supply voltage is greater than 32 VDC for two seconds.
The engine's ECM has been powered for three seconds.
The engine is not being cranked.
168-1 System Voltage Low The battery supply voltage is less than 9 VDC for two seconds.
The engine's ECM has been powered for three seconds.
The engine is not being cranked.
168-2 System Voltage intermittent/erratic The engine is running. The battery voltage falls below 9 VDC for at least .06 seconds. The voltage returns above 9 VDC.
or
Three voltage readings in the last seven seconds were below 9 VDC. The electrical power for the engine comes through a 16 amp circuit breaker, the Engine Control Switch (ECS), and the Electronic Control Module (ECM). The system receives battery voltage when the ECS is in the AUTO, START or STOP positions. A signal is provided to the ECM that senses the position of the ECS. When the ECM senses battery voltage on this input, the ECM will power up. If the voltage is removed from the input, the ECM will power down.An emergency stop for engine operation is provided in the starting system. Power to the ECM flows through the breaker for the ECM and the ECM relay. The ECM relay is energized when the ECS is in the AUTO, START or STOP positions and the emergency stop button is not activated. When the emergency stop button is activated, power is removed from the coil of the ECM relay. The contacts of the ECM relay open removing the power to the ECM.The presence of two +Battery connections and two −Battery connections to the ECM reduce harness resistance. All of these connections must be complete in order to ensure proper engine operation.With intermittent faults, you may want to bypass the engine wiring. Bypassing the wiring helps to locate the problem. If the problem is no longer present with the bypass in place, the engine wiring is faulty.
Illustration 1 g01218323
Typical schematic
Illustration 2 g01218324
P1 ECM connector
(P1-52) +Battery
(P1-53) +Battery
(P1-63) −Battery
(P1-65) −Battery
(P1-70) Keyswitch
Illustration 3 g01218327
"Connector A"
(Terminal 7) +Battery
(Terminal 9) +Battery
(Terminal 11) −Battery
(Terminal 13) −Battery
Illustration 4 g01234146
Location of ECM connectors
Illustration 5 g01218329
"Connector B"
(Terminal 13) Keyswitch Test Step 1. Inspect Electrical Connectors and Wiring
Remove electrical power from the ECM.
Thoroughly inspect the ECM connectors J1/P1. Inspect all of the other connectors. Refer to Troubleshooting, "Inspecting Electrical Connectors" for the proper procedure for inspecting system wiring.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Inspecting Electrical Connectors" for details.
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem in the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.Repair CompleteTest Step 2. Check the Voltage to the ECM
Disconnect ECM connector J1/P1.
Turn the circuit breaker for the battery to the ON position.
Turn the ECS to the STOP position.
Measure the voltage between P1-53 and P1-63.
Measure the voltage between P1-52 and P1-65.
Measure the voltage between P1-70 and P1-65. Expected Result:The voltage is 1 VDC from the voltage at the battery terminals.Results:
OK - The ECM is receiving the correct voltage.Repair: If the problem is intermittent, refer to Troubleshooting, "Inspecting Electrical Connectors".STOP
Not OK - The voltage is incorrect. The battery or the alternator may be causing the problem. Proceed to Test Step 3.Test Step 3. Check the Battery Voltage
Turn the circuit breaker for the battery to the OFF position.
Turn the ECS to the OFF position.
Measure no-load voltage at the battery terminals. Refer to Testing and Adjusting, "Test Tools for the Electrical System" for the proper procedures to check the batteries.
Load test the batteries. Use the 4C-4911 Battery Load Tester. Refer to the Operating Manual, SEHS9249. Refer to Special Instruction, SEHS7633. Expected Result:The no-load voltage at the batteries is at least 23.5 VDC, and the batteries pass the load test.Results:
OK - The battery voltage is OK and the battery passes the load test. Proceed to Test Step 4.
Not OK - The battery voltage is incorrect and/or the battery fails the load test.Repair: The batteries or the alternator are causing the problem. Recharge the batteries or replace the batteries. Verify that the original condition is resolved. Refer to Systems Operation/Testing and Adjusting for information on testing the charging system.Repair CompleteTest Step 4. Check the Voltage at the Emergency Stop Relay
Reconnect ECM connector J1/P1.
Disconnect wire 103-RD(Red) from terminal 30 of the emergency stop relay.
Turn the circuit breaker for the battery to the ON position.
Turn the ECS to the STOP position.
Measure the voltage between wire 103-RD(Red) and the −Battery terminal.
Reconnect wire 103-RD(Red) to terminal 30 of the emergency stop relay. Expected Result:The voltage is 24 3 VDC.Results:
OK - The voltage is 24 3 VDC. Proceed to Test Step 5.
Not OK - The voltage is not 24 3 VDC. Proceed to Test Step 7.Test S