No low beam head lights on 1999buick regal - 1999 Buick Regal

Do you know how to do basic automotive electrical testing ?

Headlamps Inoperative - Low Beams

Disconnect the headlamp switch.
Turn the headlamp dimmer switch to the LOW position.
Using a test light, frontprobe between the headlamp switch harness connector terminal D to ground.
Does the test light illuminate? YES - NO ?

2
Using a test light, probe between the headlamp switch harness connector terminal D to ground.
Does the test light illuminate?
--
YES - Go to Step 3
NO - Go to Step 4
3
Replace the headlamp switch. Refer to Headlamp Switch Replacement .
Has the repair been made?
--
Go to Headlight System Check
--
4
Repair a poor connection or an open in circuit 1750 between the headlamp switch and the harness connector terminal A and G201.
Has the repair been made?
--
Go to Headlight System Check
--
5
Reconnect the headlamp switch.
Using a test light, backprobe between connector C201 terminal A3 and ground.
Does the test light illuminate?
--
Go to Step 6
Go to Step 7
6
Repair a poor connection or an open in circuit 10 between the harness connector C201 terminal A3 and S221.
Has the repair been made?
--
Go to Headlight System Check
--
7
Using a test light, backprobe between connector C201 terminal A2 and ground.
Does the test light illuminate?
--
Go to Step 8
Go to Step 9
8
Replace the headlamp dimmer switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle .
Has the repair been made?
--
Go to Headlight System Check
--
9
Using a test light, backprobe between the underhood accessory wiring junction block harness connector C2 terminal F10 to ground.
Does the test light illuminate?
--
Go to Step 11
Go to Step 10
10
Replace the underhood accessory wiring junction block. Refer to Accessory Wiring Junction Block Replacement .
Has the repair been made?
--
Go to Headlight System Check
--
11
Repair a poor connection or an open in circuit 1201 between the underhood accessory wiring junction block harness connector C2 terminal F10 and connector C201 terminal A2.
Has the repair been made?
--
Go to Headlight