FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P1633



DTC P1633

CIRCUIT DESCRIPTION
The engine control module (ECM)/powertrain control module (PCM) receives 2 ignition inputs from the ignition switch, ignition 1 signal, and ignition accessory signal. The ECM/PCM receives the crank input from a serial data message from the body control module (BCM). The ECM/PCM determines the state of the ignition switch based on these 3 inputs. If the ECM/PCM detects an improper ignition accessory signal, DTC P1633 will set.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P1633 Ignition 0 Switch Circuit

CONDITIONS FOR RUNNING THE DTC
No serial data circuit problem.

CONDITIONS FOR SETTING THE DTC
The ECM/PCM detects an improper ignition accessory input voltage.

ACTION TAKEN WHEN THE DTC SETS
- The ECM/PCM will not illuminate the malfunction indicator lamp (MIL).
- The ECM/PCM will store conditions which were present when the DTC set as Failure Records only.

CONDITIONS FOR CLEARING THE DTC
- The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
- The DTC can be cleared by using the scan tool Clear DTC Information function.

TEST

Steps 1-7: