For 1990-2009 cars

### DTC P0716 - ISS Sensor Intermittent

### Circuit Description

The input speed sensor (ISS) is threaded into the transaxle case located near the transaxle fluid filter. The ISS produces an AC voltage of different amplitude and frequency depending on velocity of the input shaft. The ISS uses 8 total machined notches off the 2nd gear clutch to produce different AC voltage signals. This ISS signal is sent to the powertrain control module (PCM), which is used to determine input shaft RPM. Missing or extra pulses in a revolution of the input shaft will be interpreted as noise by the PCM. Noise may be caused by an intermittent open, short to ground, or short to voltage. The level of noise is based on engine and output shaft speed. DTC P0716 sets when ISS signal voltage at the PCM changes too rapidly indicating a noisy signal.

### DTC Parameters

DTC P0716 will set if PCM has detected ISS signal noise when:

• | The speed noise parameter = YES

• | The condition exists for longer than 0.8 seconds

• | The condition exists twice in one ignition cycle (2000)

• | The condition exists once in one ignition cycle (2001)*

• | The input speed is greater than 1400 RPM

DTC P0716 diagnostic runs continuously once the above conditions have been met.

DTC P0716 is a type A DTC for 2000, type B for 2001.*

*Applicable to vehicles built after June 2000.

### Diagnostic Aids

Use scan tool to monitor SPEED NOISE while wiggling wires. SPEED NOISE will = YES if noisy or missing ISS pulses are being received.

DTC P0716 can set due to an:

• | An intermittent open anywhere in the ISS circuit

• | An intermittent short to ground or short to voltage on circuit 1231

• | A loose sensor

• | Electromagnetic interference (EMI) caused by high current carrying wiring routed near ISS sensor wiring. EMI can alter amplitude and/or frequency of ISS signal and create invalid ISS pulses.

An intermittent open anywhere in the ISS circuit or intermittent short to ground/short to voltage on circuit 1231 will cause the TRANSMISSION ISS parameter on Scan tool to momentarily drop out.