Digital Radio Poor or No Reception

WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.

Step	Action	Values	Yes	No
Schematic Reference: Radio/Navigation System Schematics Connector End View Reference: Entertainment/Communication Connector End Views
1	Did you perform the Diagnostic System Check - Vehicle?	-	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Make sure the vehicle is outside in an area with an unobstructed view of the southern sky. Turn ON the ignition, with the engine OFF. Turn ON the radio. Tune the radio to satellite channel 1. Is the reception clear?	-	Go to Step 3	Go to Step 5
3	Tune the radio to several other satellite channels. Is the reception clear?	-	Go to Audio System Troubleshooting Hints	Go to Step 4
4	Contact XM at 1-800-852-9696 to verify customer account status or possible network problems. Did you find and correct the condition?	-	Go to Step 14	Go to Step 10
5	Contact XM at 1-800-852-9696 to verify possible network problems. Did you find and correct the condition?	-	Go to Step 14	Go to Step 6
6	With a scan tool, observe the digital radio antenna in the digital radio receiver data list. Does the scan tool indicate that the digital radio antenna is within the specified range?	1200-1800 mV or 42-118 mA	Go to Step 10	Go to Step 7
7	Disconnect the antenna cables from the digital radio receiver. Measure the voltage from the center conductor of the inboard antenna connector on the digital radio receiver to one of the case screws. Does the voltage measure within the specified range?	4.5-5.5 V	Go to Step 8	Go to Step 10
8	Test the antenna cables for the following: An open A short A high resistance Refer to Testing for Intermittent Conditions and Poor Connections . Did you find the condition?	-	Go to Step 9	Go to Step 11
9	Replace the antenna cable. Refer to Digital Radio Antenna Cable Replacement . Did you complete the replacement?	-	Go to Step 14	-
10	Inspect for poor connections at the digital radio receiver. Refer to Testing for Intermittent Conditions and Poor Connections . Did you find and correct the condition?	-	Go to Step 14	Go to Step 12
11	Inspect for poor connections at the digital radio antenna. Refer to Testing for Intermittent Conditions and Poor Connections . Did you find and correct the condition?	-	Go to Step 14	Go to Step 13
12	IMPORTANT: Always perform the setup procedure for the digital radio receiver. Refer to Digital Radio Receiver Setup . Replace the digital radio receiver. Refer to Digital Radio Receiver Replacement .Did you complete the replacement?	-	Go to Step 14	-
13	Replace the digital radio antenna. Refer to Antenna Replacement - Cellular Communications/Digital Radio . Did you complete the replacement?	-	Go to Step 14	-
14	Operate the system in order to verify the repair. Did you correct the condition?	-	System OK	Go to Step 2