D4 light blinking and hard shifting

lesliedavid48

New Member
ok... my moms 97 civic ex 1.6L sohc is having some troubles. it had the transmission replaced (with used), worked fine for a couple weeks. she replaced the radiator fan switch (a coolant sensor on the back RH of the engine). Then ever since then the D4 light has been blinking (on the dash) and vehicle seems to shift hard. i am a trained mechanic, but not honda specific. i scanned the vehicle for codes and got several. i cleared the codes then drove it till the D4 light started blinking again. scanned codes again and all the old codes came back. ---- P1382-P0700-P1753-P0720-P0730---- one is for the output shaft sensor circuit(p0720) in general. i found the output shaft speed sensor connector was loose (connector lock was broken). i shoved it down tighter then test drove it. the light never came back on.------ dad and i then took a little road trip in the car. 4 hrs later D4 light started blinking again. i stopped and cleaned the connector out, and put die-electric grease on it. now it seems worse. usually it would take a few miles of driving before the light would come on. now it comes on just moving a few feet. -----we replaced the output shaft sensor with a known good one. now the connector lock works. still the D4 light blinks.....also seems to not shift into overdrive.....

i wonder if anybody has had a similar problem? or if someone could help....
please
 

RonJ

Banned
Was the replacement transmission from other than a Civic EX?
 


lesliedavid48

New Member
we are assuming so. she asked for a transmission for a 97 civic ex and everything fit together perfectly. it worked perfectly for two weeks. once she changed the engine coolant sensor, it started acting up. ------+ last night i found the crank sensor wires have been rubbed bare by the alt belt-- no CKP engine code though.???
 

RonJ

Banned
A non-EX auto transmission will bolt up perfectly fine to the D16Y8 (EX) engine but will throw auto transmission codes.

Currently, after resetting the ECU, what codes return/repeat.

This^ is a distributor sensor code.

-P0700-P1753-P0720-P0730
These^ are auto transmission codes.
 


RonJ

Banned
once she changed the engine coolant sensor, it started acting up. ------+
The radiator fan switch plugs into the thermostat housing. Is that the sensor you replaced?

last night i found the crank sensor wires have been rubbed bare by the alt belt-- no CKP engine code though.???
Do you mean the CKF sensor behind the crank pulley? What wire colors?
 


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