4+3 overdrive switch
Thread Starter
Burning Brakes
Joined: Feb 2007
Posts: 901
Likes: 132
From: Kerrville, Texas
4+3 overdrive switch
Can anybody tell me why the overdrive switch on my 88 does not work? Overdrive seems to work properly but you can't switch it off. I tested the switch and it has continuity. thanks
Pro
Joined: Dec 2005
Posts: 709
Likes: 1
From: Lakewood Colorado
I had a broken wire between the switch and the OD. Little too close to the exhaust. Have heard others with solenoid prob and others with continuity on normally open but bad on normally closed posts of switch. Doubt it but there's a chance its the computer. Any error codes?
Pro
Joined: Dec 2005
Posts: 709
Likes: 1
From: Lakewood Colorado
Team Owner
Joined: Jan 2003
Posts: 20,305
Likes: 240
From: Summerland B.C. Canada
Maybe the "T" rod in shifter needs an adjustment to fully activate switch.
http://members.shaw.ca/agent86/OD%20Switch.pdf
http://members.shaw.ca/agent86/Overdrive-manual.pdf
http://members.shaw.ca/agent86/OD%20Switch.pdf
http://members.shaw.ca/agent86/Overdrive-manual.pdf
CF Community Team
Joined: Oct 2004
Posts: 19,363
Likes: 5,243
From: Cape Cod, Mass.
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Check your relay for the OD in the engine compartment. Sometimes the wiring to the relay gets corroded. I believe the fuel pump relay is identical.
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
Read this thread and see if it helps
http://forums.corvetteforum.com/show....php?t=1591410
Not the exact same issue but the trouble shooting will be similar.
http://forums.corvetteforum.com/show....php?t=1591410
Not the exact same issue but the trouble shooting will be similar.
