slowexcoupe

My power locks not been working for a year or so, but I finally decided to do something about it.

Fuse number 6(20A) is fine. I thought I would mention that my driver door switch is not turning on the dome light when the door is open. I know it's not the switch cause I switched the driver and pass. switches and the original drivers side switch worked fin on the pass. side

I tried the tests in the helms (p23-236) for the control unit.



Tests 1&2 checked out.
Tests 3-5 would only pass the tests with the control unit connected, by probing the back of the connector instead of the front. This is probably not right.
Test 6 failed. I could not get the actuators to operate by jumping the connectors.

I tried the door lock switch test on 23-239. The switch passed the test.


Then I tried the actuator tests on 23-238. Everything passed the test. I did notice the 4-pin connector was really greasy/nasty so I cleaned that up but it didnt help. I even tried another actuator test. I tried applying battery voltage to the same wires (step 3, p23-238), but at the control unit connector. The actuators worked as they were supposed to. This rules out (i think) a bad connection at the connector in step 3.


My diagnosis was a bad control unit since everything else checked out. So I bought a used one on ebay. I got it today, but it didn't fix my problem.

Where do I go from here?

Former User

What was the Ohm reading in test 1 and the voltage reading in test 2?

The instructions in the diagram for tests 3-5 are incorrect and should state to do the tests with the connector plugged into the control unit, as you realized.

***The instructions in the diagram for test 6 are also incorrect and should state to do the tests with the connector unplugged from the control unit. Redo test 6 this way. I suspect that this won't change the result (locks won't operate), but it's still important to verify.

Dielectric grease is often applied to connectors to insulate and protect them from corrosion.

slowexcoupe

1 & 2 on page 23-236?
1 - I didn't check the ohm reading, I had my meter set to beep if there was continuity, and there was. I can check the actual value tonight.
2 - It was above 12V. I wrote it down at home, maybe 12.7, I cant remember for sure.



I believe I effectively did this test and the locks worked. Instead of using the wht/grn & black wires at the connector as 12v source and ground, I ran jumpers from a spare battery to the wht/red and yel/red terminals. The doors locked and unlocked properly.

Former User

These results sound fine.

Your tests provide some useful information (Wht/Red wires, Yel/Red wires, and actuators are fine) but leaves the Blk ground wire untested. Redo the tests using the Blk ground wire and also test whether the Blk wire terminal in the control unit connector has continuity to body ground.

slowexcoupe

Is this different than what I did in step 1 on 23-237? There was continuity there, but I just tested some random ground point (door frame, I think) not the grounds the manual refers to (G551, G552).

I'll try step 6 from 23-237 tonight with the connector unplugged and post my results.

tlarimer

iTrader: (3)

You need to test the ground in the door lock circuit, also check the ground where it attaches to the body. If the ground is faulty, then the power locks circuit will not be completed and the door locks will not work.

Former User

You are correct.

I would do this just for confirmation.

Your door switch tested fine, but I'm surprised that the service manual does not describe door switch connector input tests. For example, in the unplugged 3P door switch connector, what voltage to body ground do you measure at the Grn/Wht and Grn/Red wire terminals? Does the Blk wire terminal have continuity to body ground?

Likewise, in the unplugged 4P driver's door actuator connector, what voltage to body ground do you measure at the Blu/Wht wire terminal? Does the Blk wire terminal have continuity to body ground?

slowexcoupe

I had continuity between the blk wire at the connector and G551, under the carpet next to the door sill.

By jumping the pins at the connector, I could not make the door actuators operate. However, If I connected the wht/red and the yel/red directly to a spare battery, they will operate. I don't understand this at all. There's 12.35V at the wht/grn wire, and continuity from the black wire to ground. What is going on there? Makes no sense to me.

Grn/Red - 12.5V momentarily, then drops and settles at 8.5V
Grn/Wht - 0V
Blk - Has continuity to ground.

Not sure which half of the connector to test (the half that runs to the actuator, or the half that runs back to the control unit). I tested the side that runs back to the control unit.

Black had continuity to ground at G551, and any other ground.
Blu/wht with control unit connected: 14V, the dropped and settled at 9.5V
Blu/wht without control unit connected: 0V

Former User

Does the Blk wire terminal in the control unit connector have continuity with the metal frame under the dash?

Odd. What method are you using to jump the pins in the connector? Can you post a picture?

If you briefly ground the Grn/Red wire pin by running a wire from it to the metal frame under the dash, do the locks unlock?

The Grn/Wht wire pin should also have voltage. Double check the voltage test. If there's still no voltage, test the Grn/Wht wire for continuity between the control unit and door switch connectors.

That's correct.

Does this Blk wire pin have continuity with the metal frame under the dash?

If you briefly ground the Blu/Wht wire pin by running a wire from it to the metal frame under the dash, do the locks lock?

motegicivic

You tested the switch right?

Also, did you check the wires in between the driver's door and inner fender, to see if any are split?

slowexcoupe

Yes. This metal plate, right?


See bottom of post.

No

Grn/Wht has no voltage. There is continuity between this pin and the grn/wht at the control unit connector. I thought that the wht/grn wire was the one that was supposed to have battery voltage.
Grn/Red only has 1.2V today for some reason.

Yes

No

Here's my methods. They're probably half wrong, and most definitely ghetto as hell. I apologize in advance.

Here's the ground side of my jumper wire. It's a copper conductor from some RG6 i had lying around. I connected it to the blk and yel/red wires


Here's the positive side:


and jumping the wht/grn and wht/red wires. Nothing happens


Which is strange since measuring voltage across these wires:


Gives you this reading:

Former User

Based on all of your test results, I'm pretty sure the connector for door lock control unit is bad.

slowexcoupe

Just the gray plastic connector itself? Can that be replaced individually, or would I need to find a whole new door harness?

Former User

You can replace the whole door harness or find the connector (cut and solder splice) or harness at a junk yard.

motegicivic

Read my number #10 post, it is common for 96-00 civics, but you never know for earlier ones too.

slowexcoupe

I'll see if I can take a look at those wires. Will I need to remove the harness to do this? Do you know if the connector at the other end is in the cabin under the dash, or do they connect between the door and the cabin?

tlarimer

iTrader: (3)

It's in between the door and the chassis, sometimes they corrode and the pins break off from the wiring inside the door jamb connector

Former User

Broken wires between the door and cabin is common, but if you look carefully at all the test results, a bad control unit connector is the best fit.

motegicivic

Open the door and you will see a black rubber boot, just pull it back and check all the wires one by one. If you want you can take off the door to make it easier.

I find it strange you are getting voltage at the grey plug. I am wondering if the control unit is bad, but you said you replaced it, but with used units? are they def the right ones for your car?

slowexcoupe

Ok, I was worried I would have to remove the fender or the door to get to it.

Me too. I'm getting battery voltage and good ground at that connector. But for some reason it's not enough voltage to operate the door actuators. I wonder if that means the wht/grn wire is split/cracked/broken somewhere.

Yes, the other control unit was used, but it off the exact same model civic as mine, except a year newer.

motegicivic

True low voltage, could be mean not enough to operate the locks. Could be split, go out and check the wires like I said.

By the way in your pics I can see the boot, right behind the hinge.

slowexcoupe

I found another pic I took. It looks to me like the protective cover over the wires is coming apart.

Former User

Look at your own results.

--->The only wire (Grn/Wht wire at driver's lock switch) that has clearly tested bad (no voltage) is contained entirely within the driver's door and doesn't pass from the door into the cabin.

^This is inconsistent with your test results. You never demonstrated insufficient voltage at the Wht/Green wire. It always showed battery voltage, right?

slowexcoupe

You don't suppose this had anything to do with my problem, do you?





Guess which pin is broken off? That's right, the wht/grn one.

motegicivic

Is that the plug going into the door from the fender? Which is broken the one on the right second down?