vj_M

I keep getting this code and the tranny won't take anymore fuel in first gear then if you let it coast it will work fine again and will shift.. this only happens after the truck is shut off...

P0720 OUTPUT SPEED SENSOR MALFUNCTION

when i clear it it won't do it before i pull away then it comes back..

what do I do any answers.?
and what caused it.?
thanks VJ

53 willys

SYMPTOM
P0720-LOW OUTPUT SPEED SENSOR - RPM ABOVE 15 MPH

WHEN MONITORED
Continuously with the ignition on, engine running, and gear selector NOT in park or neutral.

SET CONDITION
This DTC will set if the vehicle speed (reported from the CAB module) is above 24 Km/h (15 MPH) , and the monitored Output Shaft Speed is below 60 RPM for 2.6 seconds .

POSSIBLE CAUSES

• Park/neutral DTC present
• Intermittent wiring and connectors
• Output speed sensor ground circuit open
• Output speed sensor signal circuit open
• Output speed sensor ground circuit shorted to other circuits
• Output speed sensor signal circuit short to ground
• Output speed sensor signal circuit shorted to other circuits
• Output speed sensor ground circuit short to voltage
• Output speed sensor signal circuit short to voltage
• Output speed sensor
• ECM

if this is the ONLY code you have, I would say check the wiring at the speed sensor if it looks ok then I bet it it your speed sensor......I think they are under $30 bucks either way???

good luck

vj_M

So start by cleaning up the connection..? I will do that right now...

53 willys

yes and looking for any broken connections or wires
dielectric grease cant/wound not hurt either...

vj_M

ok just looked and its broken off right half of the sensor is in the tranny and the wire is just hanging there so i need a new sensor.. when I call NAPA whats the name of the part.. and are all the dodge ones the same.?

vzdude

Same sensor Dodge and Chryler have used since 89! Should be around 20 - 30 like ****** said. O.E.M. part number is 4800879. Dodge calls it an output speed sensor.

vj_M

Just picked er up 53.00$

vzdude

ouch! List price from Dodge is 20.95. Someone needs a butt whoopin! That is robery. At least you can fix it I guess.

53 willys

sometimes the dealer is cheaper for parts believe it or not!!!
glad you found the problem

vj_M

that price is Canadian..what ever tho its still cheaper then buying a new transmission.

vzdude

Canadian! That could be a big difference. I don't know anything about the conversion rate. But probably a lot closer to being priced right than it originally sounded.

Festus

Nah, our prices get stupid as soon as goods cross our borders. Sometimes double of what you guys can get stuff down there even though the dollar exchange is very close. This is why I order most of my stuff from your side of the border - even with shipping and brokerage fees, it's still usually cheaper.

vj_M

When i go to change this out is there gonna be fuild comming out ..? If so alot.?

vzdude

Less than a half quart or so. Sometimes none if it has sat long enough and not on a hill. Be ready for some though.

vj_M

how long would it have to sit for..? a few hours..? over night..? its been sitting now for about 10 hours..