B337

BCM Code B337:

BCM Circuit:

CIRCUIT DESCRIPTION:
Code B337 will set if the ignition is "ON" and the BCM has lost data communication with the programmer. The fault could be due to a loss of 12 volts power or ground to the programmer or a double open in the programmer data line, one on each side of the component. When this code is set the A/C clutch is disabled and the blower runs at a constant six volts. The "SYSTEM FAULT" message will be displayed on the DIC.

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

1. If multiple codes are present, a data line fault is indicated and should be diagnosed using the preceding multiple communication code chart.
2. This step determines if the fault is due to the power or ground circuits or the data line.
3. This step checks if the data line fault is in CKT 800 or at the programmer.
4. This step checks for ignition-3 to the programmer.

NOTES ON INTERMITTENTS:
If Code B337 shows as "History," without any other codes, then check the ignition feed, ground, and data circuits for intermittent faults. If other data codes are stored, refer to "MULTIPLE INTERMITTENT CODES" in this section.