Carrier VECTOR 1550 Series Operation & Service Manual

62-61753-217-77AlarmNO. Steps ALARM / CAUSE CORRECTIVE ACTIONP188 CHECK HEATER 2 CIRCUITThis device is checked twice in Pretrip - once in Test 2 and again in Test 8. TRIGGER-ON TEST 2: Normal amps for the 1HTCON2 contactor coil are 0.05 to 2.0 Amps(12 VDC). The circuit tests outside this range. TRIGGER-ON TEST 8: Normal amps for the 1HTCON2 heaters are 1.0 to 3.5 Amps (460 VAC). Thecircuit tests outside this range. UNIT CONTROL: Engine and standby operation: Pretrip will fail and display "PRE-TRIP FAIL ANDCOMPLETED". RESET CONDITION: Auto Reset if Pretrip is started again, or alarm may be manually reset via key-pad or by turning the unit off, then back on again.NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, clear thealarm(s). (See Note 1 Page 7-1) Operate the unit through the appropriate modes to see if any active alarm oc-curs. Continue with the steps below as necessary.1 Determine Which Test Triggered This Alarma. Review active alarm list. Make a note of all alarms.b. Clear active alarm list.c. Restart and monitor Pretrip. Stop Pretrip during Test #3 by holding = Key for6 seconds.d. Review active alarm list for Alarm188.If alarm is present, follow steps 2 thru 4 If alarm is notpresent, follow steps 5 thru 10.12 VDCCIRCUIT2 Check 1HTCON2a. Inspect heater contactor coil andwire connections.No damage to coil.No damaged or corroded pins.b. Check contactor coil resistance. Refer to Section 2.12.3 Check 1HTCON2 Amp Drawa. Check 1HTCON2 amp draw. Use Component Test Mode (Section 5.1.2) to test.Refer to Section 2.12 for amp values. View currentdraw in Data List.4 Check 1HTCON2 Wiringa. Inspect harness & control boxconnector pins & terminals. (Seewiring schematic Section 10.)See Note 2 & Note 5 on Page 7.2.No physical damage to harness.No damaged or corroded pins.5 Check Evaporator High Temperature Switch (EVHTS)a. Inspect for open EVHTS per wiringschematic Section 10.If open, replace switch as required.Additional steps on the next page.