Several codes P0733, P0734, and P1781
#1
Several codes P0733, P0734, and P1781
Hi everyone, a couple of weeks ago my 2001 Dodge Durango (147,000 miles) started to stutter. Every time I would stop the idle would drop down pass 500 and it felt and sounded like it wanted to die. The check engine light would come on and the OBD2 came out with the code P1734. This code is actually for a Honda so I didn't know where to go from there. The check engine light shut off and this morning the truck wouldn't shift into third. The engine started running a little hot so I cruised home slowly. I checked the tranny fluid and it was low so I added some fluid. Then I hooked the OBD2 back up to the truck and it gave me P0733, P0734, and P1781. Once I read online about the P0733/34 I tried manually shifting the truck. This works fine it goes right into third and fourth smoothly. The truck still wants to die if I come to an abrupt stop though. Any suggestions on how to fix this would help so much.
#2
#4
the tcm is an option but i would get in touch with use Master Tech before jumping into buying a new computer module as they tend to be expensive, he is the expert on transmissions
i would lean more towards a fluid problem or a solenoid problem myself, but im not sure so pm master tech and see what he says
i would lean more towards a fluid problem or a solenoid problem myself, but im not sure so pm master tech and see what he says
#5
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#7
Join Date: Apr 2007
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Since you have gear ratio errors in 3rd and 4th gear, I would remove the pan and inspect the side plate of the valve body. If the plate is broken and you find debris in the pan, there is a repair kit from the dealer and I'll be able to get the part number for you. If it not broken, sorry then the transmission needs to come apart.
Symptom:
P1781-OD PRESSURE SWITCH SENSE CIRCUIT
When Monitored and Set Condition:
P1781-OD PRESSURE SWITCH SENSE CIRCUIT
When Monitored: Whenever the engine is running.
Set Condition: The appropriate code is set if one of the pressure switches are open or
closed at the wrong time in a given gear.
POSSIBLE CAUSES
RELATED RELAY DTC’S PRESENT
INTERMITTENT WIRING & CONNECTORS
OD PRESSURE SWITCH SENSE CIRCUIT OPEN
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
OD PRESSURE SWITCH
TCM - OD PRESSURE SWITCH
TEST ACTION APPLICABILITY
1 NOTE: Low fluid level can be the cause of many transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the service information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC’s. Check and repair all engine DTC’s prior
to performing transmission symptom diagnostics.
With the DRBIIIt, read Transmission DTC’s. Record all DTC’s and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC’s, check and record all CVI’s.
Most DTC’s set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
Note: Verify flash level of transmission controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for applicable TSB’s related to the problem.
Perform this procedure prior to Symptom diagnosis.
Symptom:
P1781-OD PRESSURE SWITCH SENSE CIRCUIT
When Monitored and Set Condition:
P1781-OD PRESSURE SWITCH SENSE CIRCUIT
When Monitored: Whenever the engine is running.
Set Condition: The appropriate code is set if one of the pressure switches are open or
closed at the wrong time in a given gear.
POSSIBLE CAUSES
RELATED RELAY DTC’S PRESENT
INTERMITTENT WIRING & CONNECTORS
OD PRESSURE SWITCH SENSE CIRCUIT OPEN
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
OD PRESSURE SWITCH
TCM - OD PRESSURE SWITCH
TEST ACTION APPLICABILITY
1 NOTE: Low fluid level can be the cause of many transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the service information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC’s. Check and repair all engine DTC’s prior
to performing transmission symptom diagnostics.
With the DRBIIIt, read Transmission DTC’s. Record all DTC’s and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC’s, check and record all CVI’s.
Most DTC’s set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
Note: Verify flash level of transmission controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for applicable TSB’s related to the problem.
Perform this procedure prior to Symptom diagnosis.
Last edited by master tech; 08-24-2011 at 12:48 AM.
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#8
Wow thanks so much for all the suggestions. I was looking around online and I saw that you can disconnect the battery to reset the computer so I am trying that. I will let you know if it works at all. If not I will probably have my boyfriend pull the pan and check out the valve body. I will let you know what we find if anything. I had another question...the truck has been getting warmer than usual, not overheating, could this be the strain on the engine from the transmission? Thanks!
#10
I replaced the thermostat on it about 2 months ago it probably is time to flush the cooling system. I drove to work which is about 1 mile away and it shifted through all the gears. It was possibly delayed a little but I don't know if I'm thinking it's delayed because I'm really paying attention to the RPM's or if it is delayed. I am going to put my OBD2 on it and check the codes and erase then and see if the check engine light turns on again. Since tranny fluid is leaking, slowly, I'm gonna drop the pan and check the valve body out and replace the gasket, I just recently had mt fluid changed and my brother made a gasket because autozone said the Durango uses RTV sealant. We found one and I ordered it. I will let you know what happens next.