For 1990-2009 cars

# SERVICE MANUAL UPDATE-SEC. 8A VEH. SPEED SENSOR DIAGNOSIS

#### MODELS/YEARS 1989 CUTLASS CIERA

Add the following symptom to the Symptom Tables for the 1989 Cutlass Ciera Service Manual, Section 8A, pages 33-3, 33-4, 33-5 and 33-7 for the Vehicle Speed Sensor Diagnosis.

Speedometer is Do Test G inaccurate

On pages 33-4 and 33-7 insert the following test.

G:SPEEDOMETER IS INACCURATE

1. Connect a scan tool to the ALDL connector. Drive the vehicle, observe the Speedometer and compare it to the vehicle speed shown on the scan tool.

* If both the speedometer and scan tool display the same speed, check for correct tire size, VSS drive gears and ECM PROM.

* If scan tool and speedometer do not display the same speed, replace Instrument Cluster.

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