B337

Code B337:

Wiring Diagram for Code B337 - Loss Of HVAC Programmer Serial Data:

CIRCUIT DESCRIPTION:

Code B337 will set if there is a loss of serial communication with the BCM. This can occur if the HVAC loses ignition, ground or both serial data circuits.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. Step checks for power and ground up to the programmer. The test light should be "ON" when connected from ignition source to both grounds.

2. Since power and ground is available to the programmer, the source for failure is either a double open in the 800 CKT or faulty terminal contacts.