1999 ford tarus se comfort station wagon

Not sure I follow you.
The engine temp sensor sends a signal to the engine computer and the computer decides when to activate the fan relays. So if you have power to the fans you would also have power to the high or low speed relay the temp sensor is probably working. There is a third relay for the ground circuit.

Have to test or replace battery

Then have to test starter solenoid & or starter

Could be ignition switch or other items in starting system

you have a faulty alternator by the sounds of it, try this simple test, : test the voltage of the battery with the vehicle off with a simple multimeter, it should read just over 12v then test it with the car running, it should read around 14-14.5 volts if it still only reads 12v then your alternator needs replacing.

try boosting car may have enough power to turn on lights but not enough to start if starts have battery and alternator tested

Check your grounds. You can use a jumper wire from the battery ground post to the ground circuit of each component. For testing.

with this little bit of info all i can say is, start simple check your battery terminals they may have build up keeping you from getting all the juice you need to run your lights, then check all your fuses, sounds like a fuse problem, anyway start with that

take it back to the dealer, now that the problem is there, they should be able to find it.

08. [05A] HID level, telephone 12. [10A] B+ (battery voltage positive) for OBD 16. [05A] Open 20. [15A] Right headlight, low beam 05. [10A] Instruments, heated seats, cruise test plug, AC 09. [10A] Open 13. [10A] Brake lights 17. [10A] Navigation 21. [15A] Left headlight, low beam 01. [05A] Heated washer nozzle 03. [05A] Light for glove box, AC, selector lever 06. [05A] Control module comfort system 10. [05A] CD changer 14. [10A] Comfort system 18. [10A] Right headlight, high beam 22. [05A] Parking light, right 02. [10A] Turn signal system 04. [05A] License plate light 07. [10A] ABS 11. [05A] Cruise control (for automatic) 15. [10A] Instruments (for automatic) 19. [10A] Left headlight, high beam 23. [05A] Parking light, left 24. [25A] Wiper system 31. [15A] Back up lights, cruise control (automatic transmission) 38. [15A] Comfort system 25. [30A] Fresh air blower, recirculation control, AC 32. [20A] Engine control 39. [15A] Emergency flasher system 26. [30A] Rear window defogger 33. [15A] Cigarette lighter, front 40. [25A] Dual horn 27. [15A] Rear window wiper system 34. [15A] Engine control, injectors 41. [25A] Open 28. [15A] Fuel pump 35. [30A] Trailer socket 42. [25A] Open 29. [20A] Engine control 36. [15A] Fog lights 43. [00A] Open 30. [20A] Sunroof 37. [20A] Radio system, telephone 44. [30A] Heated seats
Location are marked on the fuse panel.. May need a flashlight to see them,


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Sounds like the jolt from the barrier has caused a bad ground to occur. Look for a bad ground wire around the left headlamp in or around the headlight bucket.
Tighten or replace the bad ground wire. A poor contact will cause the headlight to light dimly.

check the fuel pump itself.. if no fuel going through lines... injectors won't work.