Solenoids Are Good But Transmission Still Not Shifting
One of the things that can have you misdiagnosing your Honda Civic's automatic transmission is if its slipping.
By ‘slipping’ I mean you stick the lever in D and the engine rev's up but the vehicle doesn't move or as you're driving down the road, the automatic transmission neutralizes (and when you give the engine more gas... it only revs up but the transmission doesn't engage).
Why?... Because if your Honda Civic's automatic transmission is slipping, then replacing a transmission shift solenoid will not bring the transmission back. Only an overhaul can.
This doesn't mean you shouldn't troubleshoot the transmission trouble code making the D4 light blink.
If you've tested and found either solenoid (A/T clutch pressure control solenoid B or A/T clutch pressure control solenoid B) good and your Honda's transmission isn't slipping... yet a P1768: A/T Clutch Pressure Control Solenoid A Electrical and P1773: A/T Clutch Pressure Control Solenoid B Electrical keeps popping up, I would suggest that you:
- Check the continuity of circuit #2 between the A/T clutch pressure control solenoid in question and the PCM with a multimeter.
- Check the continuity of circuit #1 between the A/T clutch pressure control solenoid in question and the PCM with a multimeter.
The above two tests have to be done with the specific wiring diagram of your Honda and will help you eliminate a possible ‘open’ between the PCM and the solenoid you're testing.
If after testing the wiring and you find no faults, then there's a good chance that you'll have to replace the A/T clutch pressure control solenoid in question to see if replacing it solves the problem. I know this isn't something you want to hear, but in some cases there's just no other way to troubleshoot the issue (I speak from personal experience and from comments other readers have sent in).
If after testing the solenoid, its related wiring, and/or replacing the A/T clutch pressure control solenoid and the problem still persists... then you either have a bad transmission (internal mechanical/hydraulic problem) or the PCM is bad. Before you run out and buy a PCM, let me tell you that it's very, very rare for a PCM to go bad and keep the transmission from shifting (it does happen but you're more likely to get hit by lightening than to have this happen to you).
Now, if your Honda's transmission is slipping, then replacing the the A/T clutch pressure control solenoid in question isn't gonna' help bring the transmission back to normal. Slippage is a direct result of internal damage to the friction discs or hard parts. The only way to solve a slippage issue is overhauling the transmission.
More Honda Civic Test Tutorials
You can find a complete list of Honda Civic tutorials in this index: Honda 1.7L Index of Articles.
Here's a small sample of the tutorials you'll find in the index:
- How To Test The Crank Sensor (2001-2005 1.7L Honda Civic).
- Maintenance Required Light Reset (2001-05 1.7L Honda Civic).
- How To Do A Cylinder Balance Test (2001-2005 1.7L Honda).
- How To Test Trouble Code P0141 (2001-2005 Honda 1.7L).
- How To Test The TP Sensor (2001-2005 Honda 1.7L).
- How To Test Trouble Code P0135 (2001-2003 Honda 1.7L).