4+3 Stuck in OD !!!!!
Thread Starter
Heel & Toe
Joined: Jan 2008
Posts: 16
Likes: 0
From: Flat Rock MI
4+3 Stuck in OD !!!!!
Hey guys,
I have done a search on this and cant seem to find anything that helps me out.
I have an 85 C4 with 4+3 and I cant get it to come out of overdrive. The button clicks and seems to work but no deal. After it warms up (about 10 minutes) the light comes on and as soon as I go into 2nd, it hops right down into OD. When I mash the pedal down it does hop back out for a second but then right back in again after the RPM's come down.
I have heard people say change the filter and check the fluid, which I will. Is there anything else I should look for or check into?
Thanks !!
JT
I have done a search on this and cant seem to find anything that helps me out.
I have an 85 C4 with 4+3 and I cant get it to come out of overdrive. The button clicks and seems to work but no deal. After it warms up (about 10 minutes) the light comes on and as soon as I go into 2nd, it hops right down into OD. When I mash the pedal down it does hop back out for a second but then right back in again after the RPM's come down.
I have heard people say change the filter and check the fluid, which I will. Is there anything else I should look for or check into?
Thanks !!
JT
Intermediate
Joined: May 2008
Posts: 36
Likes: 0
From: Katy TX
You might have lost the connection to the O/D switch. Check wires to the O/D switch. The switch OPEN or broken wire issues an “Overdrive Request” to the ECM. If you pull out the O/D relay, you should not get O/D. The relay is located right next to the fuel pump relay, beside the vacuum brake booster.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Check the switch.the switch lets you overide ECM control of O/d.
You are not STUCK in O/d .
Everything else is working correct ,the ECM is turning O/d off and on as it is programmed to do
Last edited by rodj; May 30, 2008 at 07:01 PM.
Pro
Joined: Sep 2006
Posts: 702
Likes: 2
From: Conyers Ga
There are several inputs that control when the OD comes on one of which is temperature. It should NOT engage below 123 degrees + or - one or two degrees. Then there's the pressure switch located inside the OD itself. The relay is also a possibility. There's a chart that shows the different specs on each year. I will see if I can locate it here and post it.
Basic troubleshooting though starts with the switch itself.
Basic troubleshooting though starts with the switch itself.
Instructor
Joined: Apr 2008
Posts: 171
Likes: 1
From: west chester pennsylvania
that happened to me last week. take off the pieces around the shifter, and make sure the 2 wires from the shifter are still in tact and connected. clean the switch while your down there.
if that doesnt work. you might need to buy a new switch.
if that doesnt work. you might need to buy a new switch.
