The GM Delay Wiper System
This article is a compilation of some information I have collected on GM’s delay wiper system (as used on the 85-88 Fiero) from various sources. It is by no means complete. I appreciate any and all information you might be able to share about this error prone bugger. Some of this information may or may not be relevant to other GM vehicles, like the Firebird, Camaro, etc. Use your own judgment.
The basics
On the 1984 Fiero, GM had used a separate control module with a gazillion (well, about 8 or 10) control lines to convert a dumb wiper motor into a system with delay. The new system consists of an electronic module located inside the wiper motor housing, the wiper motor and a delay switch located inside the steering column. The delay module is accessible by removing a single screw from the wiper motor housing, then removing the cover.
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