TM-9-2320-365-20-1 LMTV Unit Maintenance Manual M1078 Series - Volume 1 Download
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e66. TRAILER BLACKOUT STOPLIGHTS DO NOT ILLUMINATE (CONT) TM 9-2320-365-20-1 2-792 Change 1 KNOWN INFO TEST OPTIONS NO YES Continuity Test or STE/ICE-R Test #91 REASON FOR QUESTION 2. Go to step 6 of this fault. CAUTION Read CAUTION on following page. Is continuity present from connector J130 socket F to relay K27 terminal 87? This question eliminates possible problems and determines where troubleshooting continues. TEST OPTIONS KNOWN INFO WARNING Read WARNING on following page. Voltage Test or STE/ICE-R Test #89 3. POSSIBLE PROBLEMS Is 24 VDC present at relay K27 terminal 30 on PDP? Towing vehicle blackout stoplights OK. Circuit breaker CB39 OK. Trailer electrical system OK. Rear lights cable assembly OK. Rear intervehicular 24 VDC (12 pin) cable OK. REASON FOR QUESTION If 24 VDC is not present, wire 1959 is faulty. NO Repair wire 1959 from K27 terminal 30 on PDP to circuit breaker CB39 terminal 4 (para 2-40) or replace WTEC II dashboard cable assembly (para 7-10) or WTEC III dashboard cable assembly (para 7-11). YES Faulty dashboard cable assembly. Faulty relay K27. POSSIBLE PROBLEMS Towing vehicle blackout stoplights OK. Circuit breaker CB39 OK. Trailer electrical system OK. Faulty dashboard cable assembly. Faulty relay K27. Faulty rear lights cable assembly. Faulty rear intervehicular 24 VDC (12 pin) cable.