GMC Topkick 2008 Primary Underhood Fuse Box / Block Circuit Breake
No. Fuse Usage 1 RR DEFOG Rear Defog 2 ENG 1 Engine 1 3 ENG 3 Engine 3 (L18/LF6/LF8) 4 PCM-B Powertrain Control Module 5 TCM Transmissions (LF8) 6 ENG 4 Engine 4 (LMM/LF6/LF8) 7 ENG 2 Engine 2 (L18/LMM) 8 HTD FUEL Heated Fuel (LMM) 9 BLANK Not Used 10 BLANK Not Used 11 NOTE 3 Fan Relay (LMM), Emissions (L18) 12 A/C COMP Air Conditioning Compressor 13 ABS 1 Anti-lock Brake System 1 14 ABS 2 Anti-lock Brake System 2 15 ABS 3 Anti-lock Brake System 3 16 ENGINE Engine 17 E/A PUMP Electronic/Automatic Pump 18 HORN Horn 19 NOTE 2 Fuel (L18/LMM), Electronic Control Module (LF6) 20 NOTE 3 Electronic Control Module (LF6) 21 STUD A Spare 22 STUD B Spare
Relay Usage NOTE 1 LMM/L18 Fuel Pump Relay IGN B RELAY I gnition Relay STARTER RELAY Starter Relay HORN RELAY Horn Relay IGN A RELAY Ignition Relay PTO/ECU* RELAY Power Take-Off/Engine Control Unit (*Diesel 7.8L LF8) REVERSE RELAY Reverse Relay FAN RELAY Fan Relay (LMM)
GMC Topkick 2008 Primary Underhood Fuse Panel / Board – Fuse Symbol Map
