Scan Tool Does Not Communicate with Low Speed GMLAN Device

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Modules connected to the low speed GMLAN serial data circuit monitor for serial data communications on the low speed GMLAN network during normal vehicle operation. Operating information and commands are exchanged among the modules.

The following modules communicate on low speed GMLAN:

* Radio, w/U32
* Digital Radio Receiver (DRR), w/U2K

Diagnostic Aids

The following conditions may cause a total loss of low speed GMLAN data communication:

* The low speed GMLAN serial data circuit is shorted to ground.
* The low speed GMLAN serial data circuit is shorted to voltage.
* An internal malfunction of a module on the low speed GMLAN network that causes a short to voltage or ground.

TEST

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