DTC P1640: Output Driver Module Circuit No. 1: Description
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Output Driver Modules (ODM) are chips that are inside the Powertrain Control Module (PCM). ODMs provide grounded outputs that control devices. Each output has an internal feedback circuit that connects to the PCM microprocessor. ODM 1 determines if the voltage or the current may cause damage to the PCM. The PCM monitors voltage through the ignition 1 input. Any incorrect current that is on a circuit to the ODM will cause the ODM to report this Diagnostic Trouble Code (DTC).