Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSSATURN2002SL1 L4-1.9L SOHC VIN 8REPAIR AND DIAGNOSISPOWERTRAIN MANAGEMENTCOMPUTERS AND CONTROL SYSTEMSVEHICLE SPEED SENSORDESCRIPTION AND OPERATION
2002 Saturn SL1 L4-1.9L SOHC VIN 8
Vehicle Speed Sensor: Description and Operation
2002 Saturn SL1 L4-1.9L SOHC VIN 8SECTION Description and Operation
Output Speed Sensor (OSS)
The OSS is threaded in the back of the transaxle case near the differential housing. The VSS produces an AC voltage of different amplitude and frequency depending on the velocity of the output shaft. The OSS produces the signal from 16 evenly spaced notches on the transaxle differential carrier. The OSS produces a readable AC voltage signal when vehicle speed is above 5 km/h (3 mph). The OSS signal is sent to the PCM, which is used to determine the rpm of the output shaft.
ODOMETER - The 055 produces 5000 readable pulses/mile between 5 and 161 km/h (3 - 120 mph), which are sent to the PCM to determine vehicle speed. The vehicle speed input is used to determine the miles the vehicle has traveled. The PCM reads the 055 signal and sends vehicle speed information to the BCM over the Class II link. The BCM in turn calculates the distance traveled and sends the information to the I/P cluster over the link. The I/P cluster increments the electronic odometer accordingly.
SPEEDOMETER - The OSS voltage pulses are sent to the PCM to determine vehicle speed. The PCM averages the vehicle speed calculations over time then sends it to the I/P cluster over the Class II link every 100 ms.
Averaging the information allows the speedometer to obtain smooth speedometer needle fluctuations.
The OSS signal is also used for many engine emission control calculations, idle speed adjustment and transaxle shift points.
The OSS is threaded in the back of the transaxle case near the differential housing. The VSS produces an AC voltage of different amplitude and frequency depending on the velocity of the output shaft. The OSS produces the signal from 16 evenly spaced notches on the transaxle differential carrier. The OSS produces a readable AC voltage signal when vehicle speed is above 5 km/h (3 mph). The OSS signal is sent to the PCM, which is used to determine the rpm of the output shaft.
ODOMETER - The 055 produces 5000 readable pulses/mile between 5 and 161 km/h (3 - 120 mph), which are sent to the PCM to determine vehicle speed. The vehicle speed input is used to determine the miles the vehicle has traveled. The PCM reads the 055 signal and sends vehicle speed information to the BCM over the Class II link. The BCM in turn calculates the distance traveled and sends the information to the I/P cluster over the link. The I/P cluster increments the electronic odometer accordingly.
SPEEDOMETER - The OSS voltage pulses are sent to the PCM to determine vehicle speed. The PCM averages the vehicle speed calculations over time then sends it to the I/P cluster over the Class II link every 100 ms.
Averaging the information allows the speedometer to obtain smooth speedometer needle fluctuations.
The OSS signal is also used for many engine emission control calculations, idle speed adjustment and transaxle shift points.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.