GASKET 9M1289 - Caterpillar

System Operation Description:The ECM receives electrical power from the Engine Control Switch (ECS) when the switch is in the AUTO, START or STOP position. A signal is provided to the ECM that senses the position of the Engine Control Switch. 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.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.Note: If your system has EMCP II, refer to Service Manual, SENR5398.
Illustration 1 g00598858
Schematic
Illustration 2 g00598859
Test Step 1. Check for Connector Damage.
Verify that the circuit breakers are not tripped.
Turn the circuit breaker for the battery to the OFF position.
Turn the ECS to the OFF/RESET position.
Check the connectors and wiring for the following problems: damage, abrasion, corrosion and incorrect attachment.Expected Result:The connectors and wiring are free of the following problems: damage, abrasion, corrosion and incorrect attachment.Results:
OK - Proceed to test step 2.
Not OK - Repair: Repair the connectors and/or wiring or replace the connectors and/or wiring. Stop.Test Step 2. Check 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 P1-6 and P1-5.Expected Result:The voltage should be 23 to 27 VDC.Results:
OK - The ECM is receiving the correct voltage. There may be an intermittent problem. Consider temporarily bypassing the engine wiring. Proceed to test step 3.
Out Of Range - The voltage is incorrect. The wiring or components between the battery and the ECM may be preventing the voltage from reaching the ECM.Repair: There is a problem in the wiring harness. Repair the connectors and/or wiring or replace the connectors and/or wiring. Stop.Test Step 3. Bypass The Wiring Harness.Note: The bypass is only for this TEST. The bypass may be left on the engine temporarily. REMOVE THE BYPASS BEFORE RELEASING THE ENGINE TO THE CUSTOMER. The ECM will be powered if the bypass switch is activated. The ECS must be placed in the START or STOP position and the bypass switch must be activated for normal engine operation. The AUTO function will not operate at this time. The bypass switch must be deactivated in order to shut down the engine.Note: Deactivate the bypass switch before performing the following connections.
Build a bypass circuit. Refer to figure 2. Use 14 AWG wire.
Connect the battery end of the bypass directly to the +Battery post.
Remove P1-6 (+Battery) from ECM connector P1. Crimp a socket pin (green stripe) to the other end of the bypass. Insert the socket into hole-6 (+Battery) of P1.Note: Use black electrical tape on all temporary connections. Wrap the connections tightly. Keep the connections clean.
After tests are complete, restore all wiring to the original condition.Expected Result:Engine operation should be normal with the bypass in place.Results:
OK - The problem is no longer present when the bypass is