1994 Dodge Ram transmission speedometer sensor and gear

87,000 MILES • 5.9L • V8 • 2WD • AUTOMATIC
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GRICK40
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I replaced the sensor and gear and reinstalled it and test drove my truck speedometer still will not work, I even pulled the unit back out and had my wife watch while I spun the gear and the speedometer work fine, so what else could it be
Aug 21, 2014 at 8:54 AM
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JACOBANDNICKOLAS
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Have you checked for trouble codes?
Aug 21, 2014 at 10:06 AM
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GRICK40
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No trouble codes either
Aug 21, 2014 at 11:10 AM
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JACOBANDNICKOLAS
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How did you check for the codes?
Aug 21, 2014 at 11:20 AM
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GRICK40
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I have a code checker
Aug 21, 2014 at 11:44 AM
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JACOBANDNICKOLAS
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Try this... Cycle the key from off to on 3 times. The 3rd time, let it in the run position (engine off). See if the check engine light begins to flash.

All trouble codes are 2 digit numbers. Count the flashes, there will be a short delay and then it will begin to flash again. That will be the 2 digit number. For example, if it flashes 2 times, delay, then 3 flashes, that is a code 23.

See if anything comes up that way. Your scanner may not read transmission codes.
Aug 21, 2014 at 11:51 AM
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GRICK40
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1-2-3-7-2-2-5-5 this I think may be two codes one is a EGR valve I changed engines and the New engine doesn't have a EGR valve on it so it throws a code
Aug 21, 2014 at 12:05 PM
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GRICK40
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Ok one is code 12 were I replaced the battery,,
Second code
Aug 21, 2014 at 12:42 PM
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JACOBANDNICKOLAS
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12 = Direct Battery input to PCM disconnected within last 50 ignition key-on cycles. If battery hasn't been disconnected, check battery power and ground connections.

37= Torque converter clutch solenoid CKT or trans temp sensor too high or low. Open or short in CKT wiring or connectors. Voltage out of range at transmission temperature sensor input. If you have this code, the check engine light should remain on.

22= ECT sensor voltage too high or too low. Most likely a poor connection or a bad sensor. NOTE: This could cause the engine air / fuel mixture to be off causing poor running conditions, starting conditions, and poor fuel mileage.

55= End of message code.

None of these are related to the function of the speedo. Take a look at the pic I attached. Is it the speedo pinion gear that you replaced? Is it turning? I assume this is a 2wd truck. If you safely place it on a rack so you can start the engine and place it in gear, does the pinion gear turn?
Aug 21, 2014 at 12:50 PM
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GRICK40
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Yes that's it exactly, when I purchased it from dodge it was a gear 33, the one that was in it before was a gear 34, they said it was the wrong gear(34) and the 33 was the correct one.
How or what do I do to fix the second code 37
Aug 21, 2014 at 1:09 PM
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JACOBANDNICKOLAS
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First, it sounds like they may have given you the wrong part for the speedo. If you spin it by hand and it works, then the speedo pinion gear isn't turning.

As far as the code 37, I would start by checking electrical connections as well as for corrosion at the plugs.
Aug 22, 2014 at 12:49 PM
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GRICK40
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Would you happen to know what the correct gear is for it, my feeling is the gear with a 34 on it was incorrect as well because it was eat up bad. Sorry to keep asking just don't want my son to end up with speeding ticket, also it was working good till something stop working, thought it was the gear sense it was clear eat up. Any advice will help me.
Aug 22, 2014 at 3:18 PM
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JACOBANDNICKOLAS
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I would start by getting the original size gear to put back in to it. As far as why it was damaged, that is a good question. However, did it work properly for a long time before the issue? Also, there are a couple different choices for me to look at when I look up the trans for this vehicle. Do you happen to know which transmission is in it?
Aug 24, 2014 at 1:55 PM
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