17 Pin Data Link Connector (DLC) - TEN GND

Early layout


Later fully populated layout (unlikely to find all terminals populated on MX-5 though)



FEN - Fault Engine
MEN - Monitor Engine
TEN - Test Engine
+B - Battery positive
GND - Ground
FAT/TAT - Fault/Test Automatic Transmission
FBS/TBS - Fault/Test Brake System (ABS)
FAC/TAC - Fault/Test Air Conditioner
FWS/TWS - Fault/Test 4 Wheel Steer
FSC/TSC - Fault/Test Speed Control (Cruise Control)

FAB/TAB - Fault/Test Air Bag
IG- - Ignition coil pulse (enables measurement of engine speed)
TFA - Test Fan
F/P - Fuel Pump (Ground terminal to run the fuel pump)

BUSA/BUSB - Used for communication
KLN - K-Line used for communication (not shown)