What this code means
P0747 may indicate that the automatic transmission pressure-control system is not behaving as expected by the PCM.
What the vehicle may do
- The vehicle may go into fail-safe operation.
- The transmission can be limited to 2nd or 5th gear when the code is stored.
- A driver may feel a harsh engagement or shift-related shock.
Possible fault areas
- ATF level, leakage, or fluid condition may be involved.
- Internal metal debris or excessive clutch material may be involved.
- Pressure switch feedback may be involved.
- The clutch pressure control solenoid and secondary valve body area may be involved.
Diagnostic path
Opening context
On this 2010 through 2017 Honda Accord with the 2.4 gas engine, P0747 is handled as a transmission hydraulic and mechanical control diagnosis. In plain language, the PCM may be seeing a pressure-control problem in the automatic transmission. The driver may notice fail-safe behavior; when P0747 is stored, the transmission does not shift to any gear other than 2nd or 5th gear. The possible fault areas can include ATF level or leakage, fluid contamination, internal clutch material or metal debris, pressure switch feedback during gear engagement, and the clutch pressure control solenoid and valve body area. Before clearing anything, save the captured data and any on-board snapshot with the HDS, then start with the basic system checks.
ATF and internal-debris check
Start with the fluid check. Warm the engine to normal operating temperature, which here means the radiator fan comes on. Then make sure the transmission is filled to the proper level and look for fluid leaks. After that, drain the ATF through a strainer and inspect what the strainer catches. If you find metal debris or excessive clutch material, the diagnostic call is to replace the transmission. If the strainer does not show metal debris or excessive clutch material, replace the ATF and continue into the verification path.
Duplicate the fault with the scan tool
Now try to duplicate the problem. Select ON mode with the engine start stop button, clear the DTC with the HDS, and start the engine. With the brake pedal held, shift to D and watch the 2nd Pressure Switch parameter on the HDS. The question is whether the 2nd Pressure Switch turns on with a shock caused by engaging gears.
Decision point
If the 2nd Pressure Switch turns on with that engagement shock, the failure is duplicated. The fault call is the A/T clutch pressure control solenoid valve A, and the repair is to replace the secondary valve body, which includes A/T clutch pressure control solenoid valve A. If the 2nd Pressure Switch does not turn on that way, treat it as an intermittent failure, and the system is OK at this time. Do not guess past that point; pause and recheck the earlier diagnostic path if the symptom or data does not line up.
Takeaway
The key on P0747 is to separate a contaminated or damaged transmission from a fault you can duplicate through pressure switch feedback during gear engagement. Check the fluid and debris first, then use the HDS verification step to decide whether the fault is present now or intermittent. For more diagnostic training, visit stepdiagnostics.com.
Final check
For this code, the diagnostic path first checks fluid condition and debris, then tries to duplicate the fault with HDS pressure switch data during gear engagement.
For more guided automotive diagnostics, visit STEP Diagnostics.
