855425A 1 Mercury THROTTLE BODY KIT

Table 1
Diagnostic Codes Table    
Code and Description     Conditions which Generate this Code     System Response    
336-7 Engine Control Switch : Not Responding Properly     Both switch inputs display open to the ECM.     The code is logged.    
Overspeed verify switch
PTO enable switch
PTO ramp up switch
PTO ramp down switch
ECM selection switchThe switches are normally open or normally closed.
Illustration 1 g01745833
Typical switch inputsTest Step 1. Check the Electrical Connectors and the Wiring
Remove electrical power from the engine ECM.
Turn the keyswitch to the OFF position.
Illustration 2 g01762573
P1 terminals for the various switches (P1-45) ECM selection (1) (P1-46) ECM selection (2) (P1-54) Overspeed verify switch (P1-56) PTO enable switch (P1-58) PTO ramp up switch (P1-60) PTO ramp down switch
Perform a 45 N (10 lb) pull test on each of the wires in the circuit for the suspect switch.
Check the allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the allen head screw on the customer connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque value.
Check the harness and wiring for abrasions and for pinch points from the battery to the ECM.Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion or of pinch points.Results:
OK - The wiring and connectors are OK. Proceed to Test Step 2.
Not OK - There is a problem with the wiring and/or a connector.Repair: Repair the wiring and/or the connector. Replace parts, if necessary. Ensure that all of the seals are properly connected. Verify that the repair eliminates the problem.STOPTest Step 2. Test the Switch for Proper Operation
Disconnect the P1 connector.
Refer to Table 2. Determine the P1 terminal for the suspect switch.
Table 2
Terminals for the Switch Inputs    
Name of the Switch    P1 Terminals    Terminals on the Interface Connector    
ECM selection (1)     45     45    
ECM selection (2)     46     46    
Overspeed verify switch     54     54    
PTO enable switch     56     56    
PTO ramp up switch     58     58    
PTO ramp down switch     60     60    
Connect a meter lead to the P1 terminal for the suspect switch. Connect the other meter lead to engine ground.Note: Wiggle the harnesses during the following measurements in order to reveal any intermittent short condition.
Measure the resistance between the P1 terminal for the suspect switch and engine ground.
Activate the switch and measure the resistance again.Expected Result:When the switch is open, the resistance measurement indicates an open circuit. When the switch is closed, the resistance measurement indicates a short circuit.Results:
OK - One resistance measurement indicates an open circuit. The other resistance measurement indicates a short circuit. The switch is operating correctly. The wiring does not have a short circuit or an open circuit.Repair: Operate the engine and check the switch for proper operation.If the switch does not operate correctly, there may be a short circuit between the circuit for the suspect switch and another circuit. Carefully reinspect the components. Refer to Troubleshooting, "Electrical Inspectors - Inspect". Locate the short circuit and make repairs.STOP
Not OK - Both resistance measurements indicate an open circuit or both resistance measurements indicate a short circuit. There is a problem with the circuit for the switch.Repair: The problem could be in the switch, in the wiring, or in a connector.Carefully reinspect the components. Refer to Troubleshooting, "Electrical Inspectors - Inspect".If the inspection does not identify the faulty component, replace the switch and test the switch again.If the problem is not resolved, repair the wiring or the connector. Replace parts, if necessary. Verify that the problem is resolved.STOP