View Full Version : ECU code#6

11-02-2002, 07:23 PM
Okay today i started my car up and had it idle. Then smoke comes from my engine and i touch the valve cover and its fine (warm). I touch the top of the radiator hose to the thermostat, its cold. the bottom one that goes to the black metal coolent pipe is lil warm. The ecu puts out code #6. ECT Sensor (Engine Coolant Temperature) defective circuit or unplugged / defective sensor.

Which one is it? the one on my thermostat (actually two) or the one on my radiator? Is my thermostat stuck open or close ? if any. SHit i got my conversion done and now this. I hate whem engines smoke. Any insight would help.

11-02-2002, 07:47 PM
The ETC should be on the thermostat housing with two wires going to it. If the top hose is cold even after the car has fully warmed up, the thermostat is stuck in the closed position.

11-02-2002, 08:33 PM
Yasu, the thing is man, i did not get it running. It was just off idle. The temp gauge on the gauge-cluster on the dash said my car was warm cause the needle was half way up. which one is it? our efi cars have 3 sensors on the thermostat.

1. Black one with just one wire
2. Green clip
3. White clip

Which one is that? i hope my thermostat is not bad man. dammit i dont wanna drain the thermostat again. Fux :(

11-02-2002, 10:21 PM
From looking at the maunal diagram, it should be TW sensor (two wires, closest the the head), then thermo switch, then the single wire sensor on the back side of the thermostat housing.

11-03-2002, 09:56 AM
Yasu, my temp gauge on the gauge cluster said my car is warmed up, but the ecu threw this code. And the top radiator hose was cold but the lower one was warm. So do u think my thermostat is stuck closed? can i just swap the internals from the carb thermostat or do u think its just better to take an efi thermo stat from the junk, swap it, see if works, if not then repair it? Thanks man.

11-03-2002, 10:54 AM
use a new thermostat, make sure its the correct temp rated one....about 89 degree's celcius i think.

Wasting ur time using second hand,as it may have a faulty wax pellet

You can test them by submerging in water...bring to the boil,pays to have thermometer, it ,(thermo), should be fully open at rated temp

If thermo OK, ECT is probably becoming faulty

11-03-2002, 11:10 AM
well the upper radiator hose is cold even when engine is warmed up. so my guess is that the thermostat just wont open up. damn thing was rusted inside. i am gonna go ahead and pull one from the junk tomorrow and see what happens with it.

11-03-2002, 11:34 AM
Just buy a new thermostat. They are only $5 and you have to change it once every few years anyways.

11-03-2002, 11:47 AM
where is the thermostat for $5????? u mean the whole thermostat is just 5 bucks?? damn, if its that dirt cheap i can get it.

11-03-2002, 02:26 PM
The thermostat is $5 at any auto store. If you are talking about the sensors, then they are more than that.

11-03-2002, 06:40 PM
yeah, thats what i thought. Lemme know what i come up with guys.

11-04-2002, 12:40 AM
ECT sensor, white socket on thermostate housing. And just go buy a new thermostate ($5-6) and the gasket. Sensor is like $30.

11-04-2002, 06:22 AM
What is that Green prug for????

My car has only 1 sensor on the thermostat housing.... I guess it's for other years. (mine came from an '89)

There is indeed a hole for that sensor but it's not drilled through nor threaded

It looks like a fan sensor to me... Can anyone confirm that?

Here is what my thermostat housing looks like.

11-04-2002, 10:52 AM
Yes it's for a fan switch. For the record, mine's an 88 coupe LXi. Let's figure out the differences.

11-04-2002, 11:48 AM
yep mine looks like the one anchocies pointed out. The one u have carot looks like the one off of a carb like i used to have. Anyways, i think the green one is for the fan which is messed up on mine, cause the fan never came on which means the Thermostat is defenitely stuck closed. so no coolent is going in. Fuck man!!!!!!!!!1 I gotta get this thing fixed.

Which sensor would put out code 6??? the black one or the white one or the green one?

11-04-2002, 12:01 PM
If you look carefully at the thermostat housing, the fan will come on even if the thermostat remains closed.

The housing I showed was from an 89 SE-i. The sensor on the SE-i was located on the radiator... It may be because Honda used 2 different radiators (Denso and another company (hitachi or NS I guess)

The carb housing is much smaller and has only a 1 wire sensor for the temp gauge. It also has a vacuum thermal switch.

Ha fuck! This makes me realise I could have used my carb thermostat housing....... oh well, better have all the EFI stuff to prevent problems.

11-04-2002, 12:13 PM
Yeah, the fan should come on regardless if the thermostate is shot.
Short the green one, the fan should come on if the fan is working. The white one is the ECT sensor for the ECU.

For the LX-i, there is another sensor at the bottom of the radiator. hmmm ....intriguing

11-04-2002, 12:15 PM
i got a sensor on the radiator (denso) and two on the the exact same thermostat as anchovies posted. Yep it was off of a 89 Lxi and so is the radiator which is the same exact same one as my trashed one.

THe funny thing is. the temp gauge on the dash said my car was warmed up, but the engine did smoke and the upper radiator hose was cold and the bottom one was a lil warm as i mentioned.

The check engine line came on and the ECu put out this code.

11-04-2002, 06:43 PM
maybe my car did not run long enough for the fan to come on. Hpefully the fan relay is fine, if not i need to swap that fuckers. and yeah, the fuses are fine, both in and out. :D

11-04-2002, 10:40 PM
Just jump the fan wires, it'll tell you at least if the fan, relay and circuit is okie.
For the fan to come on with the engine running, it takes probably..mmm...longer than 10-20mins at idle and probably 10mins if you rev it up 2-3k.

11-05-2002, 01:48 AM
OK...here's my thought's....
The ECU isn't getting the right signal from ECT.....ECU use's ECT signal for basic injector pulse width,...[amount of time injector opens and shuts]...when you first start car, because its cold, ECU knows that an enriched air/fuel mixture is needed because of signal from ECT and other sensor's.....when engine has warmed up ECU will get signals back from other sensor's as normal except ECT because thermostat hasn't opened allowing coolant to flow and sensor to operate correctly.....ECU gives you #6 code.....Does the smoke smell like fuel?....Like engine may be running abit rich?
Replace thermostat,reset ECU then see what hap's....

11-05-2002, 02:19 PM
well the code went away today after fixing my thermostat. Hahaha, it was not stuck closed, it was a bad TW plug. Changed that. and no code, engine warmed up but fan never came on. Whats wrong now???? The fans are good cause i tested them with jumping them. But no matter how hot the car gets (smokes) the fan never comes on. Is it the relay thats the culprit? I even put a new sub cooling fan relay in my fuse box cause the carb dont have it and also the fuse #12 is in place. No matter what, the fan wont come on and its been longer that 20 mts. ANywayz, the fan relay is above the coolent resevoir right?

11-05-2002, 03:48 PM
Very unlikely that both temp switches failed. Well, it might be it, swap in new ones. Unless it's still not running hot enough for the fan to come on (what's the temp reading)?

11-05-2002, 03:49 PM
The cooling fan relay is in the under hood fuse box. You can check it by swapping it with the power window relay.

11-05-2002, 07:18 PM
the temp gauge on the gauge is half way up like always it used to be (different gauge though). i dont know if the fan relay might be fucked, but i will swap it and look at it. ANywayz, whats the sub cooling fan relay? is that for the 15 mts fan on after u shuf off the engine?

dj, i like ur graphic. it looks sooo cute :D

11-05-2002, 10:32 PM
If I'm not wrong, there are 2 fan switches therefore 2 relays. Sub cooling fan should be for the switch on the thermostate housing. It controls the left fan.

11-06-2002, 07:25 AM
i dont know how far its true anchovies, cause in my car, both the fans come on the same time. In some efi cars i have seen (89) they had the subcooling fan blocked with a plastic/rubber thingie over the holder. On the older efi cars, the sub cooling fan relay was a silver (aluminum) casing that was cylinderical.

I am gonna swap the lower radiator sensor and see what happens. Which one should i short to have the fan turn on? Is it the one on the radiator or is it the one on the thermostat housing?

NOTE: Why is my lower radiator hose cold when the engine is warm and also hot??

11-06-2002, 01:55 PM
I haven't been working with the cooling system for a while, but if I remembered correctly, if you short the sensor on the thermostate housing, the left fan will turn on. If you short the sensor under the radiator, the right fan will turn on.
(OR...short the thermostate housing fan, both fans will turn on..sorry..couldn't remember)
Maybe there's blockage somewhere in the cooling passages, you said the lower hose was warm before, now it's cold. How long is the car running? How about the upper hose?

11-06-2002, 07:32 PM
I never messed with the thermostat or took it apart. I ran the car for around 10 mts till the smoke came up. i guess its just the dirt from power washing my engine and all setteled on the down pipe. anywayz, i am gonna run my engine for 20 mts to see if the fan comes on. I shrot both the sensor connectors on the thermostat and the bottom of the radiator and nothing came on. I dont know whats wrong. I will see the junkyard and see how it goes. Thanks man.

11-06-2002, 09:04 PM
might be the control module for fans playing up...is there voltage going to any of the relay contacts...with key on?

11-07-2002, 06:43 PM
the relays are fine and swapped two more to get it working, but no way. I drained all the coolent and changed the sensor on the lower one with my other one from my broken radiator. anywayz, the auto radiator will work with a manual car right??? cause i did get a radiator from an auto for my car which is manual.

i am gonna get the thermostat sensor tomorrow and see if that would work, if not i got to figure out something and hopefully someone would have come across this.

green man, what happened to your car man? how did u fix ur stuff? u got the same probs as mine right?

NOTE: i ran the car for 25 mts and it was fucking hot on the valve cover.

11-08-2002, 02:18 PM
have you checked fuse number's,1,9,12,14,....all 15amp fuse's to do with cooling fans
remove the relays and check for voltage going to connector for relays with key off,then with key on

11-08-2002, 06:16 PM
Originally posted by anchovies


Ok guys, I dont feel like reading the whole thing, but I just had that problem on my car. If you look at the picture, the plug on top or the right (brown plug) is the cooling temp. sensor and the green plug (the one on the bottom or left or green) is the Temp. gauge sensor. The problem that you have is with the cooling temp. sensor ( I think that's how you call it). Change that sensor but not the plug ( they are usually good) and you should be alright. Just make sure they change the right sensor because a mechanic here changed the wrong sensor and the problem was still there. The sensor is not that expensive, it like $15 new. So go for it dude. If somebody already told you this, you can disregard this post................. Out!

11-08-2002, 10:53 PM
Brown (actually it's supposed to be white socket) is the ECT sensor for the ECU. The green socket is the temp switch for the fan. The temp. gauge sensor is the one wire smaller sensor black socket, which you can only barely see in the pic.
Just wanted to clear it up.

11-08-2002, 11:15 PM

11-09-2002, 08:46 PM
Ype the green is the fan switch or whatever u call it and the white plug is the TW sensors and the black is the temp gauge sendor

okay here is the new find, i shorted the green plug with car runnin, no fan. I shorted the one near the bottom of the radiator, No fan then too. Checked all the fues in the engine bay fuse box, all fuses are fine, relay is working good. even got the sub cooling fan and its fuse. the fuse for the cooling fan in the cabin fuse box is good too.

What the fuck is wrong? Why wont the damn fans come on????????? Is there anythign that i gotta do????? Dude carot u did not run into this problem????