GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Ignition Off.
  2. Disconnect the instrument cluster head-up display (HUD) dimmer switch.

  3. Turn the ignition ON.

Does the (HUD) turn off ?

--

Go to Step 3

Go to Step 2

2

    • Leave the instrument cluster head-up display (HUD) dimmer switch disconnected and ignition on.
    • Use a DMM in order to measure the voltage between the instrument cluster (HUD) dimmer switch connector terminal F and ground.

Is the voltage equal to the specified value?

0 Volts

Go to Step 3

Go to Step 4

3

Use a DMM in order to measure the resistance between the instrument cluster (HUD) dimmer switch terminals A and F with the switch in the OFF position.

Is the resistance equal to the specified value?

 Ohms∞

Go to Step 6

Go to Step 5

4

  1. Repair the short to B+ in CKT 622
  2. Inspect the system.

Is the symptom still present?

--

Go to Head Up Display (HUD) System Check

System OK

5

  1. Replace the instrument cluster head-up display (HUD) dimmer switch. Refer to Head Up Display Module Replacement
  2. Inspect the system.

Is the symptom still present?

--

Go to Head Up Display (HUD) System Check

System OK

6

  1. Replace the instrument cluster head-up display (HUD) . Refer to Head Up Display Module Replacement
  2. Inspect the system.

Is the symptom still present?

Go to Head Up Display (HUD) System Check

System OK