Code P0723 indicates the Powertrain Control Module (PCM) or Transmission Control Module (TCM) has detected an intermittent signal from the output shaft speed sensor (OSS). This sensor monitors the rotational speed of the transmission output shaft to control shift timing and drive the speedometer. An intermittent signal means the electrical connection or sensor output is cutting in and out rather than failing completely.
The sensor may have an internal intermittent fault due to thermal damage, cracked solder joints, or degradation of its magnetic pickup element, causing the signal to drop out randomly while driving.
Intermittent opens, shorts to ground, or high resistance in the harness between the sensor and control module, often caused by chafing against brackets, corrosion at the connector pins, or terminals that have lost tension.
Metallic particles from normal transmission wear can accumulate on the sensor's magnetic tip, causing erratic signal generation as the debris shifts position or bridges the gap between the sensor and tone wheel.
The toothed wheel that the sensor reads may be cracked, loose on its shaft, or have damaged teeth, creating inconsistent signal patterns as it rotates past the sensor tip.
Rarely, an internal fault in the PCM or TCM may cause it to intermittently misinterpret the sensor signal or provide unstable reference voltage; this should only be considered after verifying the sensor and wiring integrity.
Short trips are possible, but the intermittent signal can cause harsh shifting, unexpected neutral conditions, or speedometer failure. Prolonged driving may cause additional transmission wear or leave you stranded if the signal fails completely.
No. This code indicates an electrical circuit or sensor issue, not internal mechanical failure of the transmission. The fix is typically replacement of the sensor or repair of the wiring harness.
Almost never. Control module failure is an uncommon cause of this specific intermittent code. Exhaustively test the sensor, wiring, and connectors first. Only consider module replacement after all other causes are eliminated and circuit integrity is confirmed with a wiring diagram.
P0720 indicates a general circuit malfunction, P0722 means no signal is detected at all, and P0723 specifically indicates the signal is cutting in and out intermittently. P0723 often suggests wiring or connection problems rather than complete sensor failure.