I have been fighting a pgm-fi light

[moonjaw2002]

for a while now and have done everything my honda manual has said to.This is on a 86 accord lxi.I am getting 6 blinks on the ecu,the manual says it is the thermo switch at the bottom of the radiator.I have tested it according to the manual and it says it is good,i still replaced it because it did not work.I have checked the wires with my test meter all the way back and found no breaks.The fans kick on and off as they should,could i be getting this code from the thermo sensor on the block.I have pulled the ground on the battery everytime i have tried a new fix and still get 6 blinks.
Mark

[Mac]

could i be getting this code from the thermo sensor on the block.I have pulled the ground on the battery everytime i have tried a new fix and still get 6 blinks.
Mark

Yep. I believe that is the code for the ECT on the engine, not the switch on the radiator.

[shepherd79]

check the wires at the plug. a lot of time the wires will brake off.

[DBMaster]

check the wires at the plug. a lot of time the wires will brake off.

This is true. It happened on my car to BOTH the ECT and the fan switch. Both are on the thermostat housing. My mechanic let me cut new plugs off old harnesses he had in the shop.

Question for the others, though. Does anyone know where you can obtain these wiring connectors without having to buy a whole harness?

[w261w261]

I don't know about an '86 for sure, but there's a coolant sensor (called a TW sensor I believe) that is probably going bad. It's located by the thermostat, costs about 20 bucks from the Honda dealer and screws right in.

[Krusty55]

There are two coolant sensors next to the thermostat housing. The one on the right is probably bad (at least it was on mine). Replacing it stopped the PGM-FI light and the 6 blink code on my 86 LX-i. It also made the car easier to start when warm. If the wires aren't broken already, be real careful pulling the plug off.

Krusty55

[DBMaster]

Also, when you unscrew the sensor from the thermostat housing you get no coolant coming out. Weird, but nice. It ends up being an easy, clean job.

[2oodoor]

Moonjaw, you said "fans" are your fans both coming on at the same time? radiator and condensor.. I think those are independant of one another, someone correct me if I am wrong there.
An ecu flashing a code about a sensor on the radiator is odd, just like someone else has said, it most likely is telling you one of the thremistors around the thrermostat is out of range. Hopefully it is just the resistance reading because of the sensor, which is an easy fix, replace the sensor and or repair connections involved. Otherwise if it still flashes after that and your thermostat is reliable (working) It could be another hot spot in the cooling system that likely could be the radiator.
You did not say anything about any symptoms, just the light flashing concern, any thing else?

DBmaster, you can use any weather proof connector on these two, three, 4, 5 wire sensors. These particular connectors are a not common as replacements unless you can find some N.O.S> somewhere... then JY parts too. You have to be carefull and use high quality connectors and not just crimp splices because some of this stuff is low voltage hi ohm. Be aware of what is ECU device and what is relay controled device, two different animals.

[moonjaw2002]

Yes both fans now come on at the same time since changing the one in the radiator.I have no other problems other than the pgm-fi light being on.The wires are good on both of the sensors and i do have a extra one handy.I also have extra pigtails if needed.
I have no trouble starting the car hot,just when it is cold it takes a few tries.Thanks

Mark
Thanks for all of your help,another question.The sensor on the thermo housing,the one on the right does it tell the ecu what the fuel mixture should be?

[salgmz]

change o2 censor

[moonjaw2002]

put a new 02 sensor in way before the 6 blinks started.6 blinks is the tw sensor.Mark