Power Seat Diagnosis
DTC B1420
CIRCUIT DESCRIPTION
Battery positive voltage is supplied at all times to the seat adjuster switch and the memory seat module (MSM)/driver position module (DPM) through the same circuit. The MSM/DPM uses this battery voltage input to determine if battery positive voltage is applied to the seat adjuster switch.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B1420 Device Voltage
CONDITIONS FOR RUNNING THE DTC
The MSM/DPM must be powered and cannot have B1327 - Battery Voltage Low as an active DTC for this DTC to set.
CONDITIONS FOR SETTING THE DTC
This DTC will set only when the MSM/DPM detects less than 3 volts from the circuit.
ACTION TAKEN WHEN THE DTC SETS
- Current and history codes are set.
- The MSM/DPM ignores all memory recall commands.
- All manual seat functions will operate.
CONDITIONS FOR CLEARING THE DTC
- The DTC will clear when the MSM/DPM detects that the voltage from the circuit is greater than 3 volts.
- The MSM/DPM will clear the history DTC after 50 fault free ignition cycles.
DIAGNOSTIC AIDS
The MSM is also known as the DPM for this vehicle.
TEST
