Code P1739

CLFOX54

MEMBER
2001 HONDA ACCORD
4 CYL
FWD
AUTOMATIC
150,000 MILES

I'm really confused. My car engine light is not on. When I am at a traffic light, my car wants to surge forward. When I put on the gas, it surges a little. Once I get going, I have no problems with the transmission shifting through gears. I took it somewhere and it came back as a P1739 code. I called the dealer and they said it was the 3rd clutch pressure switch circuit and could be replaced for about $250. I took it to the dealer and was told I need a new transmission (cost over $3,000). From what I’ve read on the Internet, I should not need a new transmission, only a replacement switch. Any reason why they think I need a new transmission? Should I take it someplace else?

1 Reply

KHLOW2008

MECHANIC
41,815 POSTS

Hi clfox54

Here are the diagnostic procedures and if the code is showing as P1739, most probably the 3rd clutch pressure switch is faulty and does not require the trans to be replaced. However if diagnistics indicates that the trans is bad, it is possible a new trans is required. However I would suggest a second or even 3rd opinion to be sure.

DTC P1739/26: 3RD CLUTCH PRESSURE SWITCH

1. Using scan tool, retrieve freeze data. Clear DTCs and road test vehicle under same conditions freeze data was recorded. If DTC returns, go to next step. If DTC does not return, problem is intermittent. Check transaxle and PCM connections.

2. Turn ignition on. Measure voltage between PCM harness connector "B" terminal No. 24 (Blue/White wire) and terminal No. 20 or 22 (Brown/Black wires). If battery voltage is not present, go to next step. If battery voltage is present, go to step 4.

3. Turn ignition off. Disconnect PCM harness connector "B". Check for continuity between PCM harness connector "B" terminal No. 24 (Blue/White wire) and ground. If continuity is present, repair short to ground in Blue/White wire. If continuity is not present, check for loose connections. Replace PCM with a known-good unit if necessary and retest.

4. Raise and support front of vehicle. Set parking brake and block rear wheels. Start engine and shift to "D3" position. Run in 3rd gear for more than 5 seconds. Measure voltage between PCM harness connector "B" terminal No. 24 (Blue/White wire) and terminal No. 20 or 22 (Brown/Black wires). If voltage is about zero volts, check for loose connections. Replace PCM with a known-good unit as necessary and retest. If voltage is not about zero volts, go to next step.

5. Turn ignition off. Disconnect 3rd clutch pressure switch connector. Turn ignition on. Measure voltage between 3rd clutch pressure switch connector and ground. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Blue/White wire between PCM harness connector "B" and 3rd clutch pressure switch
connector.

6. Measure resistance between 3rd clutch pressure switch connector (switch side) and ground. If resistance is 10 megohms or more, check for loose PCM or 3rd clutch pressure switch harness connectors. Check for loose connections. Replace PCM with a known-good unit if necessary and retest. If resistance is less than 10 megohms, replace 3rd clutch pressure switch.