GL1200 Ltd. and SEI Repair -- The Wiring Harness IF YOUR MOTORCYCLE IS RUNNING, BEFORE YOU START THIS LOOK AT THE LED'S ON THE ECU. IF THERE ARE ANY LED'S ON, GO TO THE SECTION THAT THE LED'S INDICATE THAT THE PROBLEM IS IN BEFORE YOU START RUNNING THE CHECKS IN THIS SECTION. IF YOUR MOTORCYCLE IS NOT RUNNING, AND WILL NOT START, BUT YOU DO HAVE SOME LED'S THAT STAY ON/BLINK, THEN ALSO CHECK OUT THE PROBLEMS THAT ARE REFERENCED BY THE LED'S, AND REFER TO THE TROUBLE SHOOTING GUIDE FOR REFERENCE IF YOUR MOTORCYCLE IS NOT RUNNING, BUT WHEN YOU TURN THE KEY ON, THE LED'S BLINK FOR A COUPLE OF SECONDS, BUT NO LED'S STAY ON, RELAYS #4 & #5 OPERATE, THE FUEL PUMP OPERATES FOR A FEW SECONDS, THE STARTER TURNS OVER THE ENGINE, AND YOU HAVE RUN THE CHECKS ON THE FUEL SYSTEM THEN START CHECKING OUT THE WIRING HARNESS, THE LAST HELP THAT I CAN PROVIDE. WIRING HARNESS CHECKS In this trouble shooting procedure, except as noted, the checks are made with the METER in the OHMS position. REFER TO THE ECU CONNECTOR DIAGRAM Remove the ECU from its bracket at the back fo the motorcycle. It is located under the Top Box. The ECU is held on by a bracket that has three bolts in it. One on each side near the front of the bracket, and one at the back below the top box. After removing the bracket, CAREFULLY REMOVE the ECU and CAREFULLY DISCONNECT the large connector at the side. BE CAREFUL NOT TO DAMAGE THE RUBBER DUST AND MOISTURE SHIELD THAT COVERS IT. YOU CHECKED FOR THE 12 VOLT SOURCE VOLTAGE IN A PREVIOUS PARAGRAPH, BUT IT WOULDN'T HURT TO CHECK FOR IT, AND THE +5 VOLT REFERENCE VOLTAGE AGAIN. * KEY ON - KEY ON - KEY ON - KEY ON METER IN THE VOLTAGE POSITION Check for 12 Volt source at pins # 1 and 19 to GROUND CHECKING THE REGULATED INTERNAL +5 VOLTS CAREFULLY BUT FIRMLY SEAT THE ECU CONNECTOR BACK ON THE ECU. GO TO THE T1 SENSOR AND REMOVE THE CONNECTOR FROM THE SENSOR. Measure between the Connector Terminals. You should read between 4.75 to 5.25 Volts. If you DO, The internal Voltage Regulator is working. If you DO NOT, You will have to repair or replace the ECU. REMOVE THE ECU CONNECTOR FOR THE REST OF THESE CHECKS * KEY OFF - KEY OFF - KEY OFF - KEY OFF With your Voltmeter set in the OHM's position, check for continuity between pins # 2, 16, 20, and 34 to GROUND. PINS 3, 24, AND 25 ARE ALSO LISTED AS GROUNDS, BUT THESE ARE THE REGULATED 5 VOLTS GROUNDS, AND RATHER THAN TAKE A CHANCE THAT THEY COULD BE DAMAGED BY THE BATTERY VOLTAGE IN YOUR VOLTMETER, WE WILL PASS THEM BY FOR NOW. WHEN MAKEING THESE CHECKS, IF THE INDICATED READINGS ARE NOT THERE, OR IF YOUR METER READS AT INFINITY (NO MOVEMENT), THEN CHECK THE WIRING HARNESS FOR THAT UNIT FOR OPEN OR BROKEN WIRES OR CONNECTORS. IF IT READS CLOSE TO ZERO (0), THEN CHECK THE WIRING HARNESS FOR SHORTED WIRES, AFTER UNPLUGGING THE SENSOR INVOLVED. TRACE THE WIRES THROUGH THE HARNESS TO THE SENSORS INVOLVED, CHECKING ALL THE WIRING HARNESS SUB-CONNECTORS AS YOU DO THIS. Ns Sensor Continuity Check Measure between Terminals #6 and Terminals #25 You OHM Meter should read between 297 - 363 OHM's at 68 degrees F. IF it DOES NOT, Read the Ns Sensor Document. GL/GR Sensors Continuity Check Measure between Terminals #8 and #24 (GL Sensor) Measure between Terminals #7 and #24 (GR Sensor) Your OHM Meter should read between 140 - 180 OHM's If it DOES NOT, Read the GL/GR Sensor Document. T1 Sensor Continuity Check (You are checking the harness, not the sensor) Remove the connector from the T1 Sensor, and measure from the connector back towards the engine side. between the Green/Blue wire and terminal #3 between the Grey Wire and Terminal #10 There should be continuity If NOT, read the T1 Sensor Document. Tw Sensor Continuity Check (You are checking the harness, not the sensor) Remove the connector from the Tw Sensor, measure back towards the engine side of the connector. between the RED Wire and the #28 Terminal between the Green Wire and the #3 Terminal There should be continuity. Throttle Sensor Continuity Check (Checking the harness, not the sensor) Remove the connector from the Throttle Sensor. measure back towards the engine side. Measure between the RED/WHITE wire and Terminal #29 Measure between the LIGHT GREEN wire and Terminal #11 Measure between the GREY/BLUE wire and Terminal #3 There should be continuity. PBL/PBR Sensors Continuity Check Remove the Connector(s) from the PBL/PBR Sensors FOR BOTH SENSORS Measure back towards the engine side of the connectors. Measure between the PINK wire and Terminal #29 Measure between the GREEN wire and Terminal #3 PBL Sensor Measure between the WHITE Wire and Terrminal #27 PBR Sensor Measure between the BLUE Wire and Terminal #9 There should be continuity. AIR VALVE Check Remove the connector from the Air Valve Measure back toward the engine side of the connector. Measure between the GRENN wire and Terminal #2 Measure between the BROWN wire and the OUTPUT Terminal of RELAY #5 There should be continuity. SPARK UNITS SIGNAL WIRE Check * IN BOTH UNITS Measure between GREEN and CHASSIS GROUND Measure between BLUE/WHITE and the OUTPUT of #4 Relay * IN THE RIGHT UNIT Measure between the YELLOW/BLUE wire and the YELLOW/BLUE wire at the #1 & 2 Cyl. Coil Measure between the YELLOW wire and Terminal #33 * IN THE LEFT UNIT Measure between the BLUE/YELLOW wire and the BLUE/YELLOW wire at the #3 & 4 Cyl. Coil Measure between the BLUE wire and Terminal #15 There should be continuity. FUEL INJECTORS RESISTOR Measure between the WHITE wire and one side of the INJECTOR RESISTOR, and then measure between the WHITE wire and the other side. (Located on the back Fender) The readings should be about the same. * #'s 1 & 3 INJECTORS Measure between the BLUE Wire and Terminal #17 * #'s 2 & 4 INJECTORS Measure between the YELLOW wire and Terminal #35 --------------------------------------------------------------------------- You should have checked just about all of the wiring harness at this point. If you found something wrong at any time that you were going through the wiring harness and repaired or replaced it, I hope that you tried to start the motorcycle. If it runs OK at this point, then PUT IT ALL BACK TOGETHER. IF IT STILL DOESN"T RUN, AND YOU HAVE READ AND FOLLOWED THE FIRST FEW PARAGRAPHS OF THIS SECTION, AND YOU ARE NOT GETTING ANY LED INDICATORS THAT YOU COULD FOLLOW UP ON, THEN IF YOU REFER TO THE LED CHART IT WOULD APPEAR TO ME THAT ONLY AN OPEN OR SHORTED WIRE IN THE WIRING HARNESS, THE LOSS OF THE INJECTOR SIGNALS, A BAD Ns SENSOR, BAD GL/GR SENSORS OR A BAD ECU WOULD COMPLETLY STOP THE MOTORCYCLE. SINCE I HAVE TRIED TO WRITE DOWN EVERYTHING THAT I HAVE LEARNED ON THIS MOTORCYCLE, AT THIS POINT, I REALLY DO NOT HAVE ANY MORE IDEAS AS TO WHAT ELSE COULD BE WRONG.... IF YOU DISCOVER ANY MORE, OR ANY BETTER METHODS TO RUN SOME OF THESE CHECKS MORE RELIABLY, THEN DROP ME A LINE. --------------------------------------------------------------------------- THE ONLY OTHER THING THAT I WANT TO MENTION IS THAT, SINCE I FOUND MY PROBLEM WHILE RUNNING THESE CHECKS, (I AM LOOKING FOR A PBR SENSOR) AND AFTER PRICING A NEW ECU UNIT, I WOULD REALLY LIKE TO TAKE ONE APART, AND SEE WHAT IS IN THERE. IF YOU HAVE A BAD ECU, AND NO ONE ELSE CAN/WILL FIX IT, THEN I WOULD LIKE TO GIVE IT A TRY. CONTACT ME BY E-MAIL, AND WE WILL TALK ABOUT IT. You Don't happen to have a PBr Sensor do you? mattox@indirect.com ---------------------------------------------------------------------------