GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Vivant 🢒 Body Systems 🢒 Lighting 🢒 Hazard Lamps Inoperative

Step

Action

Values

Yes

No

1

Inspect fuse F20, F8 and EF6.

Is any fuse blown?

--

Go to Step 2

Go to Step 3

2
  1. Inspect for a short circuit and repair if necessary.
  2. Replace the fuse.

Is the repair complete?

--

System OK

--

3
  1. Turn ON the ignition.
  2. Inspect the voltage at fuse F20, F8 and EF6.

Is the battery voltage available at both fuses F20, F8, and EF6 within the specified value?

11-14 V

Go to Step 4

Go to Step 7

4
  1. Turn ONthe hazard switch.
  2. Remove each of the inoperative lamps from the socket.
  3. Test each lamp socket positive terminal with a voltmeter.

Is the battery voltage pulsing at the turn signal, hazard lamp socket positive terminal within the specified value?

11-14 V

Go to Step 5

Go to Step 9

5

At each bulb socket, use an ohmmeter to measure the ground circuit.

Is the resistance equal to the specified value?

0 ohms

Go to Step 6

Go to Step 8

6

Replace any faulty turn signal/hazard bulbs.

Is the repair complete?

--

System OK

--

7

Repair the power supply circuit to fuses.

Is the repair complete?

--

System OK

--

8

Repair the open ground wires.

Is the repair complete?

--

System OK

--

9
  1. Turn ON the hazard switch.
  2. Test the blinker unit connector terminal 49a with a voltmeter.

Does the battery voltage pulsing at the blinker unit terminal 8 equal the specified value?

11-14 V

Go to Step 15

Go to Step 10

10
  1. Turn ON the hazard switch.
  2. Test the blinker unit connector terminal 49 with a voltmeter.

Is the battery voltage available at the blinker unit terminal 49 within the specified value?

11-14 V

Go to Step 11

Go to Step 14

11
  1. Disconnect the blinker unit from the connector.
  2. Use an ohmmeter to measure between ground and the connector for terminal 31 of the blinker connector.

Is the resistance equal to the specified value?

0 ohms

Go to Step 13

Go to Step 12

12

Repair the blinker unit ground circuit.

Is the repair complete?

--

System OK

--

13

Replace the faulty blinker unit.

Is the repair complete?

--

System OK

--

14
  1. Disconnect the hazard switch connector.
  2. Inspect for voltage at terminal 8.
  3. Turn ON the ignition.
  4. Inspect for voltage at terminal 10.

Is the voltage available at both terminals within the specified value?

11-14 V

Go to Step 16

Go to Step 15

15

Repair the open circuit between the hazard switch and fuses F20, F8 or EF6.

Is the repair complete?

--

System OK

--

16

With the hazard switch disconnected, use an ohmmeter to measure for an open circuit between blinker unit terminal 49 and hazard switch connector terminal 7.

Is there an open circuit?

--

Go to Step 17

Go to Step 18

17

Repair the open circuit between the hazard switch and the blinker unit.

Is the repair complete?

--

System OK

--

18
  1. Remove the hazard switch.
  2. Turn OFF the hazard switch.
  3. Use an ohmmeter to measure for continuity between terminals 7 and 10.
  4. Turn ON the hazard switch.
  5. Use an ohmmeter to measure for continuity between terminals 7 and 8.

Is the ohmmeter show the specified value for both tests?

0ohms

Go to Step 20

Go to Step 19

19

Replace the hazard switch.

Is the repair complete?

--

System OK

--

20
  1. With the hazard switch still removed for testing, turn the hazard switch to the ON position.
  2. Use an ohmmeter to measure the continuity between terminals 5, 6, and 9.

Is there continuity between terminals 5, 6, and 9?

--

Go to Step 19

Go to Step 21

21

Repair the open circuit between hazard switch and the turn signal bulbs.

Is the repair complete?

--

System OK

--