Honda Accord Dx 1990.

I was going up a hill today and the CEL turned on. I stopped and checked the codes. It gave me a code 12 (EGR ). I opened the hood and checked connections and wires and hoses around the EGR since I replaced the bypasss hose few days ago.

I did a reset on the ECU and checked again and the code is gone. CEL never turned on again.

The weird part is that when I was checking the CEL codes the S light ( sport light) was giving CODE 15. D4 didn't give any codes . I have to say I changed the TCU 6 years ago because of the TCU resistor failure (known problem in this generation of hondas) . Not the S light nor de D4 light flashes when I drive. I noticed the code by accident when I read the CEL codes. The gears change perfectly. Odometer works fine


I am planning of doing the timing belt /water pump/ etc tomorrow. Should I postpone this and check the code 15 thrown by the S light?

What would be the best course of actions. Weird thing is I would have never noticed this code if I had not checked the ECU codes .

To be sure, is code 15 kickdown switch or NM Speed Sensor ?

 

Codes 9 & 15 are the magnetic pickups in the right side cover that monitor the shaft speeds of the AT. On higher mileage trans these become fouled with ferrous material and usually just need to be wiped clean, just like the drain plug, and reinserted. Check for 400-600 Ohms at 20-degrees C. If not within spec then they may need replacement.

 

Thank you for the input. I already ordered the o-rings

Is this DIY ? I tried to get access to both speed sensors and I couldn't reach them . Do I need to lift the car?

Another puzzling question . Normally the S/d4 don't throw any blinks/flashes. I found out when I tried to read a CEL code, I saw the S light giving this code.

Is that normal? I mean, I wouldn't have noticed this code if I had not checked the CEL code?

 

It may be a stored code from a previous event, but still simple enough to check yourself. 10mm socket will access the bolts, then you will need to twist it free and work it out of the right side cover.

 

I could take out the NC speed sensor on the tranny. But the NM speed sensor ...defeated me. I took the tire out , made some space, I took the 10 mm bolt out but I could no take the sensor out. ... Gonna take to the mechanic , maybe lifting the car, there is better access to it.