Possible causes

– Faulty Engine control Module (ECM)
– Engine control Module(ECM) harness is open or shorted
– Engine control Module (ECM) cicuit poor electricl connection
– Low battery voltage

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P1698 CHRYSLER Description

Engine control Module (ECM) unable to communicate with Transmission Control Module (TCM)

CHRYSLER Technical Service Bulletins for P1698 code