U1900 Mercury Possible Causes
- Faulty / intermittent ignition switch connections
- CAN Bus wiring intermittently open/shorted to power or ground
- Faulty / intermittent connection at PCM
- Faulty electrical connections at ABS Control Module
- Faulty electrical connections at the instrument cluster
- Poor connections at the trailer brake controller/trailer connector
U1900 Mercury Tech NotesThis is typically a false/intermittent code. It can occur if:
Someone hooks up a scanner to the OBDII port while the ignition is on or while the engine is idling.
A trailer brake system is installed improperly/incorrectly on a truck with ABS (anti-lock brakes).
Cost of diagnosing the U1900 Mercury code
Labor: 1.0The cost of diagnosing the U1900 Mercury code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
When is the code detected?When the PCM, Brake Controller and Instrument Cluster are unable to communicate with each other at any time while the ignition switch is turned to the “Run” position, code U1900 sets in memory.
U1900 Mercury Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Amber ABS (Anti-lock Brakes) Light ON
- Wrench Light On