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Discussion Starter #1
Good morning. Just driving along in my 2000 Taurus 3.0L sedan, and the flashing trans indicator came on, and I have 8 codes.

P0743 Torque Converter
P0750 Shift Solenoid A
P0760 Shift Solenoid C
P1451 EVAP Control System Canister Vent Solenoid Circuit Malfunction
P0135 O2 Sensor Heater Circuit B1S1
P0141 O2 Sensor Heater Circuit B1S2
P0155 02 Sensor Heater Circuit B2S1
P0161 02 Sensor Heater Circuit B2S2

I know a single component failure can cause other codes to be recorded, just wondering if anyone is familiar with this sequence or where to start.
Thank you.
 

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Start by removing, closely inspecting, and cleaning contact points of all of the grounds that you can find.And re-connect firmly.
 

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Also check fuses in the GEM/SJB and the BJB for those circuits.

If you find a blown fuse you will need to find out why it blew. Fuses blow for a reason.
 
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Discussion Starter #7
I think its the torque converter or trans. Less likely the solenoid. The fluid is brown, smells a little burned. Original trans, fluid never changed. Shifting erratically. I am sure the other codes are just due to the problems with the TC.
 

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Discussion Starter #11
The battery is fine, I actually replaced the cabin fuse box. The first code is:

When the code P0743 is set in the Powertrain Computer, it means that the Powertrain Computer or PCM is seeing greater than a 200 RPM difference between the rotational speed of the Torque Converter and the Transmission Input Shaft. When the Torque Converter Lockup Clutch engages, there should be a 1 to 1 ratio between the Converter RPM and the Input Shaft RPM.

I am assuming that the difference in the RPM either real or perceived by the PCM could easily throw codes in other components. Its like when you have a vacuum leak and it causes codes involving other components.

My scantool does point to various causes, such as grounding, but it also lists a bad solenoid or failing TC.
 

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Well, another way out there suggestion. The ground redoing was a good one. Including the main ground
on the block by the starter and the ground strap from the engine to the firewall if it has one.
A long time ago, i had access to a donor taurus that wouldn't run that i was cannibalizing parts off of.
I wondered why a car looking in such good shape was being junked. Well, a little deeper in the cannibalization
revealed the problem. One of the main engine wiring harness was rubbing against something it should not have been
and it cut through the cable can shorted out wires. This can go for wiring melted against exhaust components too.
It sometimes takes a very careful inspection removing some of the top of the engine to fully look for issues like this.
All it takes is one careless mechanic in a past repair not putting wiring back where it should have been to make the
car into a ticking time bomb to fail.
 

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Good morning. Just driving along in my 2000 Taurus 3.0L sedan, and the flashing trans indicator came on, and I have 8 codes.

P0743 Torque Converter
P0750 Shift Solenoid A
P0760 Shift Solenoid C
P1451 EVAP Control System Canister Vent Solenoid Circuit Malfunction
P0135 O2 Sensor Heater Circuit B1S1
P0141 O2 Sensor Heater Circuit B1S2
P0155 02 Sensor Heater Circuit B2S1
P0161 02 Sensor Heater Circuit B2S2

I know a single component failure can cause other codes to be recorded, just wondering if anyone is familiar with this sequence or where to start.
Thank you.
The EVAP code and the o2 codes are circuit malfunctions. While you are right in thinking one issue can trigger the others, I'd take the previous advice of checking grounds, connections, look for corrosion, etc. Assuming all these codes came at once, and none were pre-existing.
 

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Discussion Starter #16
The EVAP code and the o2 codes are circuit malfunctions. While you are right in thinking one issue can trigger the others, I'd take the previous advice of checking grounds, connections, look for corrosion, etc. Assuming all these codes came at once, and none were pre-existing.
I made a little progress, I did look around for any damaged wires and also checked several electrical connectors and found that the electrical connector going into the trans for the solenoids had some fluid in it. Not sure how it got there. I cleaned that out and now the check engine light does not come on, but am still getting the flashing trans warning light and trans errors, and 02 sensor errors.
 

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There should be a ground line that bolts to the side of the engine, probably on the same side of engine as the belt. Find it and inspect it good. Sometimes it can hang close to the exhaust and get burned up a bit on the underside. Happened to my 2003. Otherwise you might have use a multimeter and start checking maybe one of those sensor harnesses for proper signals.
 

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Discussion Starter #18
Thanks. I removed the side trans cover, and started testing the solenoids. So far I have found that the number #1 shift solenoid is bad - shorted internally. The TCCS tests ok. Will check the other two solenoids, but I think #1 solenoid is the culprit.
 

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Discussion Starter #19
Problem solved. Bad #1 shift solenoid and blown fuse #28 in the engine compartment (includes Transmission Shift Solenoid.)

The liquid I found in the transmission case connector must have shorted out the #1 solenoid and blown the fuse. I replaced #1 and #2 shift solenoids ($19 each at Autozone) (#2 shift solenoid tested ok but looked a little dark as if burned) and replaced the fuse. AOK now - back to normal.
 
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