KA24E Owners - Need A Favor

[KiLLeR2001]

I'm kinda pulling my hair out over here trying to figure out a minor issue with my Coolant Temperature Sensor circuit, so I need a favor.

I need for someone with a multimeter to check the voltage that is coming out of the CTS harness (with it unplugged from the sensor). Ignition must be ON. I'm pretty sure it is suppose to be outputting 5V but I am only getting 4.88V. I checked the continuity of the ground and the signal wire to ECU and they both have 0 ohms of resistance. I tried another ECU and I still get the 4.88V output.

There is around 1.51 kOhms of resistance within the CTS circuit and I'm wondering if thats normal. Both ECUs have around the same values.

Any help would be appreciated, thanks.

[godrifttoday]

Buy a cheap 5 dollar harbor freight

[KiLLeR2001]

I have a multimeter, I just need to see what voltage values other people are reading.

[tauntdevil]

Nevermind, mine is different from KA24E. I have KA24DE which is just one wire. Sorry :(

[KiLLeR2001]

^ Both KA24DE and KA24E have a 2 wire CTS sensor. The 1 wire temperature switch is for the gauge cluster only.

http://i94.photobucket.com/albums/l115/Fireplug240/coolanttemp.jpg

(The red plug)

[tauntdevil]

With ignition turned on (one down from the car being turned on.) it read 0.55v

[cotbu]

I think your voltage of 4.88 is good, it's a 5v approximation system. so if you where above 5v or say around 4v it could be a problem. Are you getting code 13, and have you followed the testing procedure in the fsm? The sensor could be bad or is it new or something?

[KiLLeR2001]

Yes, getting code 13 and I replaced the sensor and it is within spec per FSM. I've tried another ECU and no change. I've checked the resistance of each wire from the CTS harness plug to the ECU plug and there are 0 ohms resistance.

The CTS circuit spits out 1.51 kOhms resistance which I wonder if thats within spec as well (both ECUs yielded this).

[locoluna825]

The 1.51 kohms of resistance that u say your getting in the circuit is the reading from the pin out on the ecu ??? Also if the ground wire to the coolant temperature was completly severed somewhere within the harness wouldn't it still give of a 0 for a resistance reading, have u looked about a foot into the harness for the cts connector to see if the wiring is ok. That section of the harness gets very brittle the constant heat from sitting inbetween the head And the intake...

I went round and round with a injector leak code givin off by my ecu on my single cam. I bought new injectors, seals, tried different ecu's and then it still didn't go away till I bought all new pigtails for the injectors, cut the old brittle green connectors off and soldered the new ones into the harness.

[KiLLeR2001]

Yes, its reading 1.51 kohms from the ECU pinout. Not only did I test the circuit with the ground on the CTS harness but a chassis ground as well.

[mr.nismo.]

isnt the sensor based on resistance? as the sensor gets hotter the resistance is less allowing more voltage to go through? car being cold should be low voltage. if the full 5v is going through the ecu thinks that bitch is getting hot probably. are you always at 1100 rpms or so? not connected on the sensor the 4.88 is fine. did you do a test with the car on and cts plugged in while cold?

[MrSanchez925]

is there any corrosion on the actual connector?

[cotbu]

I think I would depin the harness at the ecu and run test wires, to rule out the wiring, This shit will drive you insane, don't let it. What's the chances of having 2 bad ecu's?

[KiLLeR2001]

isnt the sensor based on resistance? as the sensor gets hotter the resistance is less allowing more voltage to go through? car being cold should be low voltage. if the full 5v is going through the ecu thinks that bitch is getting hot probably. are you always at 1100 rpms or so? not connected on the sensor the 4.88 is fine. did you do a test with the car on and cts plugged in while cold?

Yes, the sensor is fine. It's the resistance within the CTS circuit I'm concerned of (generated by the ECU). Sometimes it takes forever for the car to start up, other times it starts right up. I'm getting error code 13 on the ECU.

is there any corrosion on the actual connector?

There was a little but I cleaned it up and tested resistance of both wires from the harness down to the ECU plug, and also tested body chassis ground with the CTS signal wire and yielded the same results.

[KiLLeR2001]

I think I would depin the harness at the ecu and run test wires, to rule out the wiring, This shit will drive you insane, don't let it. What's the chances of having 2 bad ecu's?

I did this, the wires are fine.

[MrSanchez925]

Ohm testing wires isnt very accurate or a good judge on wether a wire is good or not.

Because the wire can be down to one strand left and still yeild the same results when tested.

I'm sure you have done this but ill ask anyways just in case, have you cleared the codes??

[KiLLeR2001]

Went to a friends house to test out his KA24DE. He's outputting 4.89V on his harness, so I feel better in that aspect. Upon further inspecting the signal wire for the CTS, I noticed that the wire is pretty dull looking and feeling harder than normal. Most likely I will need to replace this wire.

[locoluna825]

Its that heat from the intake mani and head, the harness gets to bake right in there for the past 20 years. Replace that section of the CTS wiring or just run new wires completly. I will bet money that will fix your issue.

Hell! if your friends nice enough and you think you can do it. Borrow his whole engine bay harness... XD

[alexander240]

^
what the fack?