LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1599 (Power Sun Roof) >> Diagnostic Information and Procedures >> Power Sunroof Inoperative

Power Sunroof Inoperative

WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Power Sunroof Inoperative

Step Action Value(s) Yes No
Schematic Reference: Power Sunroof Schematics 
1 Did you perform the Power Sunroof Diagnostic System Check? - Go to Step 2  Go to Diagnostic System Check - Power Sunroof 
2 Operate the power sunroof.
Does the system operate normally?		 - Go to Testing for Intermittent Conditions and Poor Connections Go to Step 3 
3
  1. Turn the ignition ON with the engine OFF.
  2. Disconnect the sunroof switch from the harness connector.
  3. Measure the reference voltage of the sunroof switch open signal circuit at the sunroof switch harness connector to a good ground.
Does the voltage measure near the specified value?		 4.5-5.5 V Go to Step 4  Go to Step 11 
4 Measure the reference voltage of the sunroof switch close signal circuit at the sunroof switch harness connector to a good ground.
Does the voltage measure near the specified value?		 4.5-5.5 V Go to Step 5  Go to Step 17 
5 Measure the reference voltage between the sunroof switch close signal circuit and the low reference circuit at the sunroof switch harness connector.
Does the voltage measure near the specified value?		 4.5-5.5 V Go to Step 6  Go to Step 21 
6
  1. Connect a fused jumper wire to the sunroof switch low reference circuit of the sunroof switch harness connector.
  2. Observe the position of the sunroof glass, try to operate the system by connecting the other end of the fused jumper wire to either the :
    • Sunroof switch open signal circuit
    • Sunroof switch close signal circuit
Does the system operate normally?		 - Go to Step 36  Go to Step 7 
7
  1. Remove the fused jumper wire.
  2. Connect the sunroof switch to the harness connector.
  3. Measure the reference voltage between the sunroof switch close signal circuit and the low reference circuit at the sunroof switch harness connector.
  4. While observing the sunroof switch close signal circuit reference voltage, operate the sunroof switch to the open position.
Does the sunroof switch close signal circuit reference voltage measure near the specified value?		 4.5-5.5 V Go to Step 8  Go to Step 16 
8
  1. Disconnect the sunroof module harness connector, that contains the battery positive circuit.
  2. Turn ignition to ON, engine OFF.
  3. Measure the battery positive voltage circuit at the sunroof module harness connector to a good ground.
Does the voltage measure near the specified value?		 B+ Go to Step 9  Go to Step 29 
9
  1. Turn the ignition OFF.
  2. Connect the sunroof module harness connector that contains the battery positive voltage circuit to the sunroof module.
  3. Disconnect the sunroof motor inline harness connector.
  4. Turn ignition ON, with engine OFF.
  5. Connect a test lamp between the sunroof motor open control and motor close control circuits at the inline harness connector, module side of the sunroof motor.
Does the test lamp illuminate?		 - Go to Step 43  Go to Step 10 
10
  1. Connect a test lamp between the sunroof motor open control and motor close control circuits at the inline harness connector, module side of the sunroof motor.
  2. While observing the test lamp and depending on the position of the sunroof glass, press the sunroof switch to the available positions.
Does the test lamp illuminate with each command?		 - Go to Step 38  Go to Step 22 
11 Did the reference voltage of the sunroof switch open signal circuit measure near the specified value? B+ Go to Step 12  Go to Step 13 
12 Measure the reference voltage of the sunroof switch close signal circuit to a good ground.
Did the reference voltage of the sunroof switch close signal circuit measure near the specified value?		 B+ Go to Step 15  Go to Step 28 
13 Measure the reference voltage of the sunroof close signal circuit at the sunroof switch harness connector to a good ground.
Does the voltage measure near the specified value?		 4.5-5.5 V Go to Step 18  Go to Step 14 
14
  1. Disconnect the sunroof module harness connector that has the RAP supply voltage circuit.
  2. Measure the sunroof RAP supply voltage circuit at the sunroof module harness connector to a good ground.
Does the voltage measure near the specified value?		 B+ Go to Step 37  Go to Step 33 
15 Measure between the sunroof RAP supply voltage circuit and the ground circuit at the sunroof module harness connector.
Does the voltage measure near the specified value?		 B+ Go to Step 37  Go to Step 40 
16 Measure the resistance between the sunroof switch open signal and close signal circuits. Refer to Circuit Testing in Wiring Systems.
Does the resistance measure near the specified value?		 OL Go to Step 43  Go to Step 39 
17 Did the reference voltage of the sunroof close signal circuit measure near the specified value? B+ Go to Step 20  Go to Step 19 
18 Test for an open, high resistance or short to ground in the sunroof switch open signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 37 
19 Test for an open, high resistance or short to ground in the sunroof switch close signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 37 
20 Test the sunroof switch close signal circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 43 
21 Test the sunroof switch low reference circuit for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 37 
22 Did the test lamp illuminate with one command? - Go to Step 23  Go to Step 24 
23 Is the sunroof glass in either the full open or full vent position? - Go to Step 44  Go to Step 43 
24 Connect a test lamp between B+ and the sunroof motor open control circuit at the sunroof motor inline harness connector.
Does the test lamp illuminate?		 - Go to Step 25  Go to Step 27 
25 Connect a test lamp between B+ and the sunroof motor close control circuit at the sunroof motor inline harness connector.
Does the test lamp illuminate?		 - Go to Step 43  Go to Step 26 
26 Test the sunroof motor close control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 37 
27 Test the sunroof motor open control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 37 
28 Test the sunroof switch open signal circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 43 
29 Test for an open, high resistance or short to ground in the sunroof battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 45  Go to Step 30 
30 Test both of the sunroof motor control circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 31 
31
  1. Disconnect the inline connector to the sunroof motor.
  2. Measure the resistance between the sunroof motor open control and close control circuits at the sunroof module harness connector. Refer to Circuit TestingCircuit Testing in Wiring Systems.
Does the resistance measure near the specified value?		 1-3Ω Go to Step 41  Go to Step 32 
32
  1. Replace SUNROOF fuse.
  2. Connect a test lamp between the sunroof motor control circuits at the inline harness connector to the sunroof motor, sunroof module side.
  3. Turn the ignition ON, with the engine OFF.
  4. Observing the position of the sunroof glass, press the sunroof switch to the available positions.
Does the test lamp illuminate?		 - Go to Step 44  Go to Step 43 
33 Is the RAP supply voltage being supplied directly from the BCM? - Go to Step 34  Go to Step 35 
34 Test for an open in the RAP supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 45  Go to Retained Accessory Power (RAP) Inoperative (with relay) or Retained Accessory Power (RAP) Inoperative (No Relay Class 2)
35 Test for an open or short to ground in the RAP supply voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 45  Go to Retained Accessory Power (RAP) Inoperative (with relay) or Retained Accessory Power (RAP) Inoperative (No Relay Class 2)
36 Inspect for a poor connection at the sunroof switch and harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 42 
37 Inspect for a poor connection at the sunroof module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 43 
38 Inspect for a poor connection at the sunroof motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 45  Go to Step 44 
39 Repair a short between the sunroof switch open signal and close signal circuits. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 45  -
40 Repair the ground circuit of the sunroof module for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 45  -
41 Repair the short between the sunroof motor open control and close control circuits. Refer to Wiring Repairs in Wiring Systems.
Did you complete the replacement.		 - Go to Step 45  -
42 Replace the power sunroof switch. Refer to Sunroof Switch Replacement .
Did you complete the replacement?		 - Go to Step 45  -
43 Replace the sunroof module. Refer to Power Sunroof Module Replacement .
Did you complete the replacement?		 - Go to Step 45  -
44 Replace the sunroof motor. Refer to Power Sunroof Motor Replacement .
Did you complete the replacement?		 - Go to Step 45  -
45
  1. Turn OFF the ignition.
  2. Reconnect all previously disconnected components.
  3. Replace the SUNROOF fuse, if necessary.
  4. Operate the system in order to verify the repair.
Did you correct the condition?		 - System OK Go to Step 3 
scientia non olet · About LEMON Manuals