TM  9-2320-280-20-1 REFERENCE  INFORMATION GLOWPLUGS If the engine cranks ok (or starts), then the batteries are good enough for testing the glowplugs. If the engine starts, shut it off. You can use STE/lCE Test 10 to measure cranking speed. The engine should crank at least 100 RPM in cold weather and at least 180 RPM in warm weather. NOTE The  WAIT-TO-START  lamp  is  NOT  diagnosed  in this section. If the lamp does not work property, the glowplug circuit may be affecting its operation. Run these tests to check out the glowplug circuit. If the lamp still does not work properly, go to the INSTRUMENTS section for a full diagnosis of the lamp’s problem. WARNING Disconnect negative battery cable before disconnecting and reconnecting protective control box harness. There is battery voltage at the PCS at all times. Failure to disconnect battery cable will result in damage to equipment or injury to personnel. BAD CONNECTIONS ARE THE MOST COMMON Sometimes, just disconnecting, cleaning and reconnecting will solve a problem. BE THOROUGH ! The time you save may be your own. Refer to the functional flow schematic  and  check  the  following 1. BATTERY - make sure all connections are dean and tight, including the shuntand power stud. 2. PROTECTIVE CONTROL BOX - unscrew BOTH connectors and look for bent or broken pins, pins pushed out of their socket, or dirt and corrosion in the connections. 3. GLOWPLUG CONTROLLER - pop the controller connector off (squeeze the sides) and check the pins in both the controller and the connector. Look for bent, broken or pushed out pins, dirt or corrosion. Check for broken wires at the connector. Take note that pin 2 of the glowplugs controller connector has no pin in it. 4. GLOWPLUGS - Check that all the glowplug wires are snug. Don’t just look with your eyes. Many problems  are solved by Iooking with your fingers to be sure a connection is snug. The glowplugs first come ON when the engine temperature is below 120 °F (49°C) and the rotary switch is turned to “RUN”. They stay ON for up to 9 seconds and then go OFF. They will stay OFF for about 7-15 seconds then come ON BATTERY  CURRENT MULTIMETER 1. Set the voltmeter to a DC volts scale of about 1 volt. 2. Connect the BLACK lead to the battery side of the current shunt and the RED lead to the other end of the current shunt. 3. Currant shunt voltage is proportional to battery current, 100 millivolts = 1000 amps. To get current, multiply millivolts x 10. BATTERY  CURRENT STE/ICE-R TEST 80 1. Start Test 80, battery currant. 2. Displayed reading is in amps. The reading will be greater then 30 amps, depending on how many accessories you have on. again for about 1 second. NOTE To check for glowplug current draw, start STE/lCE-R Test 80, battery current. Turn off all accessories (lights, heater, wipers etc). STE/lCE-R should immediately measure at least 74 amps. Take note, however, that if all your glowplugs are working, the current draw should be close to or more than 100 amps, especially if it’s cold. If it’s near freezing and the glowplugs only draw 75-80 amps, you probably have a few bad glowplugs. 2-305