Diagnostic Fault Information
WARNING: This page is about a different car, the 2007 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Scan Tool Does Not Communicate with High Speed GMLAN Device
| Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance | ||
|---|---|---|---|---|---|---|
| High speed GMLAN serial data bus (+) | 1 | 2(1) | 1 | - | ||
| High speed GMLAN serial data bus (-) | 1 | 2(1) | 1 | - | ||
| Ground (DLC, terminal 5) | - | 1 | - | - | ||
|
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| No communication on any high speed GMLAN module | ||||||
| An open in only one high speed GMLAN serial data circuit may allow degraded communication between the modules | ||||||