overdrive will not function
overdrive will not function
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Joined: Sep 2009
Posts: 69
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From: Montana
Chris,
I have the same problem with my 1990. I've been told to check these things first. Confirm that the OD solenoid will engage, that the torque converter will lock up (I'm guessing yours has one) that the OD part of the tranny isn't just worn out, and then the computer is receiving a signal for OD and engaging. Mine is going to the shop on tuesday, so I'll let you know what they say about my situation.
I have the same problem with my 1990. I've been told to check these things first. Confirm that the OD solenoid will engage, that the torque converter will lock up (I'm guessing yours has one) that the OD part of the tranny isn't just worn out, and then the computer is receiving a signal for OD and engaging. Mine is going to the shop on tuesday, so I'll let you know what they say about my situation.
Record Breaker
Joined: May 2008
Posts: 1,174
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From: North TX
Chris, your van has a TCM (Transmission Control Module) which is the transmission computer. Is your Check Engine lamp on? If so have the codes pulled. You will need a code scanner that can do more than the simple code reading in order to pull the codes from the transmission module.
Rookie
Joined: Sep 2009
Posts: 69
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From: Montana
Chris,
Have you solved your OD problem yet? Mine turned out to be in the wiring. The tranny guy says some of the wires are melted and missing. So I'm dead in the water unless anyone has a wiring schematic they can message me. At this point it would cost to much to have a shop try to fix it. Better luck with yours.
Have you solved your OD problem yet? Mine turned out to be in the wiring. The tranny guy says some of the wires are melted and missing. So I'm dead in the water unless anyone has a wiring schematic they can message me. At this point it would cost to much to have a shop try to fix it. Better luck with yours.
Record Breaker
Joined: May 2008
Posts: 1,174
Likes: 1
From: North TX
Is it for the 90 van or another one?
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Rookie
Joined: Sep 2009
Posts: 69
Likes: 0
From: Montana
MAR,
this is on the 1990 B250. The hot wire going from the tranny up to a plug near the PCM is missing. The plug is melted inside where the hot lead should be. He said it would take 2 bypass switches to turn on the OD, one for the OD solenoid and one for the TC. Not sure if that's correct. He said it has the A500 tranny. Is it possible to ever find a wiring harness for one of these vans to replace this? Other wires have been spliced by a previous owner. Could be a nightmare.
this is on the 1990 B250. The hot wire going from the tranny up to a plug near the PCM is missing. The plug is melted inside where the hot lead should be. He said it would take 2 bypass switches to turn on the OD, one for the OD solenoid and one for the TC. Not sure if that's correct. He said it has the A500 tranny. Is it possible to ever find a wiring harness for one of these vans to replace this? Other wires have been spliced by a previous owner. Could be a nightmare.
Record Breaker
Joined: Aug 2007
Posts: 1,146
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I think you should get the FSM from Leeanne. I imagine it would have wiring diagrams for the overdrive and lock/up circuits.
The plugs, and connectors are there to facilitate production. The plugs/ connectors can be bypassed with new wire. The important part is completion of the circuits from the PCM to the transmission.
Print up this ECM pin readout.
http://minimopar.knizefamily.net/ecu/smec-1988-tbi.html
Could help out the tranny tech.
The plugs, and connectors are there to facilitate production. The plugs/ connectors can be bypassed with new wire. The important part is completion of the circuits from the PCM to the transmission.
Print up this ECM pin readout.
http://minimopar.knizefamily.net/ecu/smec-1988-tbi.html
Could help out the tranny tech.