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Speedometer - Momentary Drop With Flashers On

File In Section: 8 - Chassis/Body Electrical
Bulletin No.: 46-83-04
Date: October, 1994

Subject:
Speedometer Momentary Drop when Turning on Park Lamps, Turn Signals or Hazard Flashers (Send I/P Cluster to Delco Repair Station)

Models:
1993-94 Chevrolet and GMC Truck C/K Models
1994 Chevrolet and GMC Truck S/T Pickup Models

Condition

Some speedometers in the above vehicles may momentarily drop when the turn signal, park lamp, or hazard flasher is turned on. This condition often occurs at speeds over 60 miles per hour.

Cause

Slight system voltage drop when the extra load from the lights is added.

Correction

Remove the instrument cluster and send it to the local Delco Repair Station. Repair stations are aware of the condition and have parts available to repair the cluster. They will add a capacitor to the power circuit to assure a consistent power flow during power up of the above mentioned lamps. Be sure to clearly describe the condition on the Delco Repair Order accompanying the cluster.





Warranty Information

For vehicles repaired under warranty, use: