Workhard1107

Hi all, desperately seeking help. My crv wouldnt shift past second gear. It would shift fine until I drove it a few miles then it wouldnt go into gear at all unless I cut car off and back on. My mechanic uncle suggested just buying used tranny. Installed tranny and still same problem. I got the p0730 and p0740 codes. Fluid is fine, lock up solenoid is fine, did ohm test and used jumper wire to make sure solenoids were clicking and reading correct ohms. Could it be the trans cooler not working considering the problems dont start until car has been driven long enough to warm up? Any suggestions would be GREATLY appreciated as this is my only means of transportation at the moment.

UK-Kev

Hello,
Hope this helps you.

Kev

What does this mean?
OBD Code P0730refers to
This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows: Torque converter slip ratio = A x C/B A: Output shaft revolution signal from speed sensor (revolution sensor) B: Engine speed signal from Engine Control Module (ECM) C: Gear ratio determined as gear position which TCM supposes If the actual gear position is higher than the position supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.
Symptoms
Possible sumptoms of OBD code P0730
- Engine Light ON (or Service Engine Soon Warning Light) - Incorrect transmission shifting
Causes
Possible causes of OBD code P0730
- Low transmission fluid level - Dirty transmission fluid - Shift solenoids - Shift solenoids harness or connectors - Transmission mechanical problems - Transmission hydraulic control circuit The Error code is generally activated on detection of the following conditions: The TCM has detected that the transmission is trying to mechanically shift to a lower gear than intended
What does this mean?
OBD Code P0740refers to
The torque converter clutch solenoid valve is activated, with the gear in D4, by the Transmission Control Module (TCM) in response to signals sent from the vehicle speed and the Engine Control Module (ECM). Lock-up piston operation will then be controlled. When the torque converter clutch solenoid valve is activated, the torque converter lockup clutch will engage creating a 1 to 1 RPM ratio between the transmission input shaft and the rotational speed of the torque converter. Lock-up operation, however, is prohibited when A/T fluid temperature is too low. When the accelerator pedal is depressed (less than 2/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.
Symptoms
Possible sumptoms of OBD code P0740
- Engine Light ON (or Service Engine Soon Warning Light) - Transmission shift shock - Vehicle may not shift into the highest gear
Causes
Possible causes of OBD code P0740
- Low transmission fluid level - Dirty transmission fluid - Faulty torque converter clutch solenoid valve - Torque converter clutch solenoid valve harness or connectors - Torque converter clutch solenoid valve circuit is open or shorted The Error code is generally activated on detection of the following conditions: Diagnostic trouble code P0740 is detected when TCM detects an improper voltage drop when it tries to operate the solenoid valve.

Workhard1107

Thanks kev. Ive read that and I guess I have to start checking wires and connectors.Any links for help on that?