B1083

B1083-HVAC MUX SWITCH HIGH (GATEWAY)

B1083-HVAC MUX Switch High (Gateway):

WHEN MONITORED
With the ignition on.

SET CONDITION
The Gateway Module will set this DTC if it detects excessive current on the (C18) A/C Select circuit.

POSSIBLE CAUSES
- (C18) A/C select circuit shorted to other circuits
- Gateway module
- Powertrain control module (PCM)

Diagnostic Test

1. VERIFY DTC B1083-HVAC MUX SWITCH HIGH IS ACTIVE

Turn the ignition on.
With the scan tool, read Gateway DTCs.

Q: Does the scan tool display active: B1083-HVAC MUX SWITCH HIGH?

YES: Go To 2
NO: Go To 4




2. CHECK FOR A SHORTED GATEWAY MODULE

Turn the ignition off.
Disconnect the Gateway Module C2 harness connector.
Connect the positive lead of an ammeter to the (C18) A/C Select circuit in the Gateway Module C2 harness connector and the negative lead to a good clean chassis ground.
Turn the ignition on.

Q: Is the reading above 0.06 amps?

YES: Go To 3
NO: Replace the Gateway Module. Perform the GATEWAY VERIFICATION TEST - VER 1. Gateway Verification Test - Ver 1

3. CHECK THE (C18) A/C SELECT CIRCUIT FOR A SHORT TO OTHER CIRCUITS

Turn the ignition off.
Using the wiring diagram/schematic as a guide, inspect the related wiring and connectors for chafed, pierced, pinched, and partially broken wires, and for broken, bent, pushed out, corroded, and contaminated terminals. Repair as necessary.

Q: Were any problems found?

YES: Repair as necessary. Perform the GATEWAY VERIFICATION TEST - VER 1. Gateway Verification Test - Ver 1
NO: Replace and program the Powertrain Control Module (PCM). Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

4. TEST FOR INTERMITTENT CONDITION

NOTE: The condition that set this DTC is not present at this time. The following may help in identifying the cause of the intermittent condition.

Check the Technical Service Bulletins (TSBs) for related concerns.
Using the scan tool, erase TIPM DTCs.
Turn the ignition off, wait 10 seconds, then turn the ignition on.
Monitor the scan tool for DTCs while wiggling the related wiring harness.
Turn the ignition off.
Using the wiring diagram/schematic as a guide, inspect the related wiring and connectors for chafed, pierced, pinched, and partially broken wires, and for broken, bent, pushed out, corroded, and contaminated terminals. Repair as necessary.
If numerous DTC were set, use the wiring diagram/schematic to check for common ground and supply circuits.

Q: Were any problems found?

YES: Repair as necessary. Perform the GATEWAY VERIFICATION TEST - VER 1. Gateway Verification Test - Ver 1
NO: Test Complete.