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DTC 16

DTC 16 VSS Buffer Fault:




Vehicle Speed Sensor (VSS) Circuit:






CIRCUIT DESCRIPTION
This DTC concerns a loss of 2002 pulses per mile to the Powertrain Control Module (PCM) terminal "F13". This may be caused by loss of power to the Vehicle Speed Sensor (VSS) buffer or an open or grounded signal line.

DTC 16 WILL SET WHEN
^ Less than 1 mph.
^ 1200 to 4400 RPM.
^ Throttle angle less than 2%.
^ Engine Coolant Temperature (ECT) greater than 60°C (140°F).
^ Manifold Absolute Pressure (MAP) less than or equal to 25.6 kPa (7.6 inches of mercury).
^ CKT 1697 open or grounded.
^ All conditions must be met for 3 seconds.

ACTION TAKEN (PCM WILL DEFAULT TO)
The PCM will turn "ON" the MIL (Malfunction indicator Lamp).

DTC 16 WILL CLEAR WHEN
Conditions for fault are no longer present and Tech 1 "Clear DTCs" function is used or 50 ignition switch keycycles have passed with no further faults or ignition switch is turned "OFF" and fuse #9 is removed for 10 seconds.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This tests for B+ at VSS buffer.
2. This tests for proper ground path for vehicle speed sensor signal buffer.
3. This tests for vehicle speed sensor signal buffer signal to PCM.
4. This test checks for faulty connections and a faulty VSS buffer.

DIAGNOSTIC AIDS
Check connections at VSS buffer and PCM. If DTC 72 is also set, refer to DTC 72 Vehicle Speed Sensor (VSS) Circuit Loss. Testing and Inspection