Code Definition

B1894 — Wiper Rear Motor Speed Sense Circuit Failure

System: Body  |  Type: Manufacturer-Specific  |  Make: Generic

About B1894

B1894 is a manufacturer-specific body diagnostic trouble code. It belongs to the B-prefix family of codes, which covers body, interior, airbag, or comfort-electronics faults.

When B1894 is stored, the module has detected an electrical-circuit fault in the wiring, connector, or driver associated with the named component.

Scanning & clearing: Body (B) codes are often stored in the body control module, airbag module, or climate module. A basic OBD-II tool usually will not read body codes — an enhanced or OEM-level scan tool is typically required.

B1894 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.

Code Information

The Body Control Module (BCM), rear electronic module, or dedicated rear wiper control module monitors the rear wiper motor speed by reading a feedback signal from a hall effect sensor or commutator pulse pickup integrated within the wiper motor assembly. DTC B1894 sets when the controlling module commands the rear wiper to run but does not see a valid speed feedback pulse stream on the sense circuit, or detects a continuous open or short on that line. The speed sense signal is used by the module to confirm motor rotation, manage park position, and control intermittent and variable speed wipin...

Join TaT to view the complete code information and diagnostic details.

Quick Facts