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Discussion Starter · #1 ·
Using direct scan, i can see that ECM is stuck in 4th gear all the time, even if i go into park/neutral, both P/N and 4th is still displayed. Where is the 4th gear wire?
 

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You could unplug the four pin connector from the side of the trans, see if the indication goes away--helps to narrow down the problem.
 

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pin C8 (lt blue) at the ecm to pin B at the trans

but i guess you want a diagram

you have the service manual so turn to section 8a- 21-3

do you have a brf trans ?
 

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Good diagrams. My gues would be, since your 3rd gear indicator isn't stuck on, the wiring's probably still intact, and possibly the connection on the 4th gear pressure switch on the valve body may have come loose.
But that would take a tranny pan pull to verify/fix.
Here's a quick check. Since those switches are N.C. (normally closed) and attached to ground, then just measure pin B at the tranny connector for continuity to ground. I'd bet it's open (not grounded) indicating a "no connection" condition.
 

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would he not just have to drop the pan to check the switches and wires. 3rd gear switch and 4th gear are the same part # but 2 different switches which can be changed without pulling the trans..at least that was what I was told from my last DS file 3rd gear was on and off a # of times and it was reccomended that I change both
 

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sean he said

TurboDave said:
But that would take a tranny pan pull to verify/fix.
.
so yep dropping the pan is all thats need to get at the switches

wooshes car is a hybrid of sorts so depending on which trans he has he may have no connection to pin b
 

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ok so what trans does he have if he running DS it has to be an 87 ecm and probally a 200r4
 

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Discussion Starter · #10 · (Edited)
You are right pacecarta, i have 200r4 OZ tranny (olds V8), which only has 4th gear switch.(no 3rd)
Only 3 wires in a tranny plug. But i'll check for ground continuity, that might be the problem, i probably missed that wire somewhere... :crazy:
 

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gbsean said:
would he not just have to drop the pan to check the switches and wires. 3rd gear switch and 4th gear are the same part # but 2 different switches which can be changed without pulling the trans..at least that was what I was told from my last DS file 3rd gear was on and off a # of times and it was reccomended that I change both
Yes, I mearly mentioned using a meter to check the wire first, before having to go through the incredibly messy hassle of pulling the pan.
 

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Discussion Starter · #12 ·
TurboDave said:
Yes, I mearly mentioned using a meter to check the wire first, before having to go through the incredibly messy hassle of pulling the pan.
heeheh, i installed drain plug last time i had to change fluid, should be easier now!
 

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pacecarta said:
sean he said



so yep dropping the pan is all thats need to get at the switches

wooshes car is a hybrid of sorts so depending on which trans he has he may have no connection to pin b


i missed the "pan" part sorry read it as pull the trans... :eek:
 
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