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Which way do you have the line on the diode face, and what are you using the diodes for again?
Sorry, forgot to answer this. The line side of the diodes is facing the peripheral wires (door and trunk wires) the non line side was facing the alarm.
Using the diodes to isolate each line attached to a single negative input on the alarm. This is supposed to prevent the trunk light from lighting up when either door opens up or if there is a door light, prevents the open door light from lighting up when the trunk is opened.
GRN/RED from the dome light passes through the ICU where it turns into GRN/BLU (or whatever colour is at the driver door dome light switch). The ICU pass-through is required for the key-in & door-open feature.
My first guess is the alarm is incorrectly wired, and is grounding the GRN/RED when it's not supposed to. Possibly a diode issue. I've seen it where the dome ground is wired to the trunk light ground but these aren't diode isolated so when the door is opened the trunk light goes on. This will correctly set off the alarm when a door or the trunk is opened and the alarm is set but yeah it's wrong.
The way GRN/RED runs is something like this: From the dome light, down the A-pillar, to a 2-pin connector kinda sandwiched between the left side of the dashboard and the body (C701/C420). Above or nearby the hole that the door wires exit through to the door. GRN/RED splits after this connector to go to the ICU and to the passenger side dome switch. It runs along rear harness under the carpet, between the driver's seat and the door, to about behind the lower seat belt mounting point, then turns to run behind the rear passenger footwell carpet over to the switch. The other GRN/RED at the split enters the ICU and exits again as GRN/BLU then follows the same harness path but just to the driver's side door switch.
Tapping in to the GRN/RED anywhere along its length will provide the necessary trigger. However, it must be diode-isolated from the trunk-open ground. These are usually tied in to the same "door-open" trigger on the alarm brain. If this is the problem, of course. Even if it's not, my sense is still that GRN/RED is grounded prior to the door switch.
Pretty sure the trunk is separate but it has been a while.
It definitely is, but when *some* people wire the alarm, they tie the two together without diodes to trigger the alarm (for the door-open sensor), and in the process fudge up the existing car wiring.
TomCat should see if the dome light works properly when the trunk is popped open.
Yeah I usually look for the wiring that goes to the lighting in the trunk and connect to the ground there and BOOM trunk trigger, so its separate. Older alarms only had a few trigger wires so for them to wire the trunk, door and hood pins together DOES require a diode. Newer alarms have separate triggers for each now so a diode isn't needed,
Good to know. When I installed one around 2012 it didn't have separate lines for these. I'm guessing TomCat is dealing with an older alarm that might have this same issue.
As far as I can tell, the drivers door is not grounded so it's after the ICU from the drivers door switch. I haven't tested the passenger side switch wire to see if it is showing ground yet but will.
I'm using the solid green wire in the cluster harness for my trunk trigger. And yes, it's an older alarm with 1 negative trigger wire and 1 instant negative trigger wire. I am using diodes to keep the door and trunk triggers isolated. When I took the diodes out and just connected the door to the alarm neg trigger wire, didn't work as it's grounded at all times at the moment as mentioned before, but worked just fine when I tied it to the green trunk wire (hatch glass technically). I think if it was tied together, the green wire would also be constantly grounded and the trunk light would always be on.
I think I have a short somewhere between the dome light and the ICU on the green/red door wire. I thought I had found the C701/C420 connector but looks like I missed it as you mention it's a 2 pin connector with the white/blue and the green/red wire that then works to the ICU in the main harness.
I'm hoping I don't have to rip out the dash or pull the sound deadening material to get to the main harness running under the carpet from driver to passenger side.
Thank you again deschlong, that was very helpful information you posted up above! Highly appreciated! I was studying the FSM and ETM but it's not the easiest to piece together for somethings, like the dome light.
I'll post up any updates if I find anything not already mentioned. Cheers!
Okay, I tested all the wires to ground and could not get continuity. Plugged everything back in and together, still could not get continuity to ground. So I'm confident there is not a short to ground anywhere.
I then started fiddling with the drivers door switch and watching the dome light (has LED bulb). When I was checking resistance from my green/red wire to ground I was getting negative resistance so I switched to DC volts and found when door is closed, I'm reading 700 millivolts on my green/red wire with bulb in. Door open I read 7+ volts with the bulb in. When I turn dome light to off or I pull the bulb out. I cannot get continuity to ground regardless of door open or closed on the green/red wire.
I think the ICU might be the problem. I checked the part number and it's the correct ICU but has been replaced with a new part number so is likely the original. It seems the ICU is letting voltage bleed through to the ground wire (green/red) and isn't providing ground to the green/red unless the circuit is completed with a bulb installed on the dome light. If the light is switched to off, the green/red never is seen as ground and that doesn't seem right as that wire should work as a negative trigger for the alarm.
Please let me know if you notice any flaws in my thoughts or if I am mistaken on any part. I am wondering if the low resistance of the LED dome light bulb caused the ICU to eventually fail. I will see about grabbing a regular bulb when I grab an ICU from the salvage yard this weekend.
Don't you own another 5G Civic? Try temporarily swapping the ICU. If not, jumper the GRN/RED and GRN/BLU on the ICU connector when it's unplugged. This bypasses the ICU and the driver's dome light switch will operate like the passenger one does. This test will tell you if the ICU is indeed the problem if the dome light functions properly without it.
Also, have you disconnected the alarm connections to the dome? To eliminate the variable.
If you do get another ICU, note that you have a number of options that give you additional features. Door-open from a 6G Civic or 3G Intégra, door-open + rear int wiper from a 1G CR-V.
Other tests if the ICU is not the problem:
Unplug the connector at the ICU.
Check for continuity between the dome GRN/RED and ICU GRN/RED at the connector. Post result.
Check for continuity between the dome and GRN/RED at the passenger side door switch GRN/RED. Post result.
Check for continuity between ICU GRN/RED GRN/BLU at the connector and at the driver's side door switch GRN/BLU. Post result.
Last edited by deschlong; 06-13-2019 at 11:12 PM.
Reason: typo
Don't you own another 5G Civic? Try temporarily swapping the ICU. If not, jumper the GRN/RED and GRN/BLU on the ICU connector when it's unplugged. This bypasses the ICU and the driver's dome light switch will operate like the passenger one does. This test will tell you if the ICU is indeed the problem if the dome light functions properly without it.
Also, have you disconnected the alarm connections to the dome? To eliminate the variable.
If you do get another ICU, note that you have a number of options that give you additional features. Door-open from a 6G Civic or 3G Intégra, door-open + rear int wiper from a 1G CR-V.
Other tests if the ICU is not the problem:
Unplug the connector at the ICU.
Check for continuity between the dome GRN/RED and ICU GRN/RED at the connector. Post result.
Check for continuity between the dome and GRN/RED at the passenger side door switch GRN/RED. Post result.
Check for continuity between ICU GRN/RED at the connector at the driver's side door switch GRN/BLU. Post result.
I do but wife has it at work and needs it from time to time.
I was going to run to the store and get a regular bulb to get the LED out of the equation. I also have the later CRV ICU's the one with the internal head light chime but I would need to sit down and re-figure out the couple of repins I figured out on the ignition system. If I recall your write up the crv you had an external chime and was only from the 98, I think mine are from 99+
And yes, I unhooked the alarm from the setup and just ran the wire on the trunk to find it works normally and have not moved it back to the dome while I isolate the door wires and ICU stuff.
I will do the above tests and report back as well as get the LED bulb out of the dome light.
On #4, the green/red is one pin on the ICU connector and the green/blue is another. I'm assuming you want to see no continuity and this test is with the connector unplugged from the ICU?
Okay, I don't have access to another 5th get ICU at the moment.
I have continuity from ICU green /red to pillar green/red, also ICU to dome green/red and ICU to passenger green/red. I also have continuity from dome to passenger green/red. I do not have continuity from green/blue to any green/red regardless if connector is in ICU or not.
And dome light is operating normally.
With dome light set for door activate, I read 12 volts from pillar green/red to ground when door closed, 910Milli volt with door open. This seems normal.
Where it does not seem normal is put dome light to off. Dome no longer has any path to ground. Continuity to ground at pillar green/red is not there regardless if door is open or closed. There is a flash of low resistance (120ohm) for a millisecond when door opens, then goes back infinite resistance.
I was under the impression there should be ground present as the alarm is not supposed to be reliant on dome light switch settings.....
That is true, the trigger should still go off even if the dome light is off. Once the trigger wire receives a ground signal it sounds the alarm. I might have to check my wires to see whats
That is true, the trigger should still go off even if the dome light is off. Once the trigger wire receives a ground signal it sounds the alarm. I might have to check my wires to see whats
I know the trigger wire works as the green trunk wire receives ground and sets off alarm regardless if key is in ignition or car is on etc.
This is what caused me to think the ICU is faulty. That and that even with door closed on door activated dome the led had slight illumination. So some power is slipping through when door is closed and ICU is not receiving ground trigger from door.
Oops #4 had a typo, I meant continuity between GRN/BLU at door and GRN/BLU at ICU connector. I'll fix it.
So you're saying the dome works properly if you jumper GRN/RED and GRN/BLU at the ICU connector.
I'm partial to agreeing with you on the ICU diagnosis. There's a diode in there that's rooted. Now's the time to install the CRV ICU, then.
I forgot to do the jumper at the ICU connector. I'll do that after work tonight. I did check and do have continuity of the green/blue from door to ICU connector. I did check that.
I wish I knew what I did with my CRV notes. I'll have to print off the fsm sheets again. Things got lost in the move 2 years ago.
Addendum
-----------------------------------------
I didn't do anything with the car tonight. Long week and pretty sore. I did print off a couple of the CRV fsm pages to realize, deschlong's old crv ICU write up was using the unique 97 CRV ICU and when I was grabbing them I had the more prevalent 98-00's available. Now sitting down looking at the connectors on paper, I remember about the deciphering I was doing. 10 pin to 15 pin conversion. Also realized I need to print off the CRV ICU schematic to piece together the wires.
I think I might grab another 95 civic ICU at the yard Sunday unless I get off early tomorrow and can do it then. I can then quickly isolate if the ICU is the bad link in the equation and fall back to that if I'm not able to re-decipher the pin outs and wire routes in a timely fashion. I definitely agree, right now is the time to do it though as all the under dash wiring is openly exposed right now as is the column wiring. This weekend is crunch time and I'm work OT so we'll see how it goes.
And don't worry, I didn't forget, I still need to do the short the green/blue to the green/red on the ICU connector and see if the dome light operates normally. I'll be doing that before any other ICU goes in, which ever one it will be.
Well, I spent some time on the car after getting off work today and running to pick a part. Managed to find an ICU from a 95 hatch that had the rear washer and intermittent front wiper.
Before I put the ICU in I shorted green/blue and green/red (A2 and A3) of the ICU connector together and tested with the following results.
Dome Light set to Off
A-Pillar Grn/Rd to Ground
No voltage Door Open or Door Closed
Continuity Door Open
No Continuity Door Closed
Dome Light set to Door Activated
A-Pillar Grn/Red to Ground
12 Volt Door Closed
90 mVolt Door Open
No Continuity Door Closed
1K Ohm (continuity) Door Open
Dome Light set to On
A-Pillar Grn/Red to Ground
No Voltage Door Open or Door Closed
No Continuity Door Closed
Continuity Door Open
Everything seem to check out so I put the new ICU in and begin testing. Alarm started working fine. I then added the diodes and finalized the install. I now have a extremely hard to get to alarm that triggers when any door is open when alarmed. Once I get the hood pins in I will run that in on the battery side and connect it to the negative instant trigger wire that wasn't used prior.
On another front. I started redoing the CRV ICU research I did and I ran into a pretty significant problem being I've wired the alarm to the dome light door trigger ground wire. Looking at the 98-00 CRV ICU schematic, the ICU doesn't directly control the dome light. I didn't look further yet but it seems to me the ICU ties into the keyless entry control unit and I suspect it controls the dome light. This poses quite a challenge to get the additional functionality and maintain my current alarm setup.
I'll provide what I pieced together so far and follow with the CRV schematic from the FSM and then the 5th gen Civic schematic for comparison.
Everything looks above as totally compatible but looking at both schematics, there is no dome light accommodations on the CRV schematic..... This poses a significant problem and will also make door activated dome lighting a challenge.
As for the rear washer stuff, I still need to pull that up as I believe those wires from the column run elsewhere on a the Civic while the CRV ran them through the ICU.
CRV Schemetic (2 pages)
And now the 5th gen Civic schematic:
As can be seen, there seems to be a challenge keeping the dome light functionality with upgrading to the 98-00 CRV ICU....
Hahahaha, I'm such and idiot.... The diodes are exactly the same and it doesn't matter if the CRV doesn't have the same wire setup.... duh! The ICU will still do the same thing as it's internal setup with diodes is the same so when drivers door grounds out, it passed onto the passenger line and in the civic, that means the dome light.........
Sometimes certain details just don't click and I get myself all confused on the wrong details (in this case the wrong vehicles wiring).
Now to continue digging up the rear washer connections, I think that's where I needed to depin and move to the ICU if I recall but I need to verify and re-familiarize myself with that part again.
This weekend I spent probably about 15 hours putting the car back together including doing the valve lash so I could burp the coolant and set ignition timing. Unfortunately I have to drop the transmission as it doesn't sound good now that it has the proper fluid in it. I think they used heavy gear oil to pad it enough you didn't here it clunking internally. Stethoscope put the loudest of the sound on the back casing so I suspect it's the rear bearings on the primary shaft that has issue.
Anyways, in putting her back together and swapping out the wiper stalk for one with the intermittent setting I noticed the VX dash harness is missing plugs like C430 which is the rear window wash/wiper plug that is present even on the cars that don't have the read wiper. Usually it's plugged into the back of the stock in a dummy holder spot if I recall.
Needless to say, it's going to be a significant addition and a lot of added work to get the rear wiper going.
Also in my beginnings of research, I am thinking for the cars that already have the C430 plug, we can use those 5 wires (6 pin plug) for the ICU maybe.
98-00 CRV ICU connector (B1-B15)
B1 - Blu/Wht - Wiper motor - (Civic A9 - Same color)
B2 - Red/Blu - Driver Seat Belt switch - (Civic A4 - Same color)
The part I haven't pieced together yet is the (As) notation. On the CRV one of the 2 motor wires has the (As) notation and the one front wiper motor wires on the Civic ICU has the notation. The Civic ETM doesn't seem to clarify the notation. On the CRV it would be helpful to know as it probably differentiates the two wires going to the rear wiper motor. I think I can piece it together by seeing where the wire marked (As) goes, if it is powering the motor or the electromechanical mechanism of the park run of the motor....
Rear wiper/washer switch for the Civic has a 5 wire (6 pin) connector C430 on the wiper stalk with the following wires and destinations.
Pin 1 - Grn - Rear wiper motor/motor
Pin 2 - LtGrn/Blk - Rear wiper motor/park-run electromechanical
Pin 3 - Blk - Ground
Pin 4 - Grn/Blk - Power to Fuse 14 of under dash fusebox
Pin 5 - Not used
Pin 6 - Rear washer motor
Tomorrow I'll post up some picks of redoing the foam seals on the heater blower and the intermediate air channel as well as the replacement of the passenger door vapor barrier. These were parts of the re-assembly over the weekend. Also I seem to have broken the stereo when adding the factory plug and conversion harness so I'll have to look at that wiring again to see where I went south.
She's on her own 4 feet at the moment. But will be going back on stands so I can swap in my DX tranny for the time being. The VX is still working, I'd like to keep it that way.
Hahahaha, I'm such and idiot.... The diodes are exactly the same and it doesn't matter if the CRV doesn't have the same wire setup.... duh! The ICU will still do the same thing as it's internal setup with diodes is the same so when drivers door grounds out, it passed onto the passenger line and in the civic, that means the dome light.........
Sometimes certain details just don't click and I get myself all confused on the wrong details (in this case the wrong vehicles wiring).
Not sure if this is what you're getting at here but you want to connect your VX's GRN/RED from A3 to where the CR-V's LT GRN/RED wire was at B13.
Yes the VX what the only CDM hatch that wasn't wired or pre-wired for the rear wiper from the switch to the washer tank, sadly. But luckily this wiring is easy to find on other hatchbacks (even 96-00 or the CR-V, though these may be different colours).
Not sure if this is what you're getting at here but you want to connect your VX's GRN/RED from A3 to where the CR-V's LT GRN/RED wire was at B13.
Yes the VX what the only CDM hatch that wasn't wired or pre-wired for the rear wiper from the switch to the washer tank, sadly. But luckily this wiring is easy to find on other hatchbacks (even 96-00 or the CR-V, though these may be different colours).
No, I already knew that as listed in the first list.
I was getting hung up looking at the CRV wiring and not seeing a dome light in the schematic and started thinking the ICU wouldn't allow my alarm to operate..... I spent about 45 minutes doing up the post and posted, then it clicked in about the diodes in the CRV ICU are setup exactly the same with some additional "reminder" circuitry and also, the CRV wiring doesn't apply. The ICU in the Civic will operate the same and the same dome wires will act the same etc etc.
Since I had already posted, I just edited the post with the laughter at myself and the short ending addition.
There's a 95 civic hatch at our salvage yard that I can harvest the wiring and washer tubing etc from. The wing is the wrong color though. The VX wing doesn't have the cut out for the sprayer. I'll have to keep my eye open for a 92 or 93 green hatch CDM CX/DX or Si.
I'm not in a rush at the moment. I have to put my CX/DX tranny in as I don't want to push the unhealthy sounding VX tranny to destruction. I need to get this car drive able sooner instead of later. Then work on upgrades etc.
Anyways, as promised yesterday, some photo's of some of the work over the weekend. Come to think of it, I probably put in 18 or more hours in on the car this past weekend. 8am to 8pm Sunday.
Since I had the heater blower motor out and the middle conduit, the 25+ year old foam seals disintegrate on contact. I went to home depot and got some 1/4 inch thick foam weatherstripping tape in charcoal color.
This first photo is the remnants of the seal replacement. Some of the old foam tape, with next to no foam attached as it crumbles at the slightest touch. Some of the protective non stick backing to the new tape, to all the crap caught in the blower motor I dumped to the floor.
New seal on the blower motor.
New seal on the conduit. After I realized I can't put it in first and it has to go in after I get the blower motor in. Yet you have to drop the blower motor to get this conduit out usually as the left bottom clip portion doesn't unclip worth a beans and usually needs to slide off once the blower is dropped. So I dropped this again and went the proper order for re-assembly.
Glove box back in place.
Blower and conduit all sealed up and in place.
The other side of the conduit, everything sitting perfectly behind the glove box.
Then the other thing that has always bothered me, every Civic I've pulled the door panels on, someone has cut the vapor barrier to do some fix or addition and they always screw it up leaving it gaping open. Since I started working for a contractor I have access to thick 3 or 4 mil poly and so since the passenger door panel was off, I used the tuck tape (used in construction vapor barrier applications) to redo the vapor barrier since I had the panel off to fix the passenger inside door lock/handle. The lock lever was broken off and they had tied a zip tie to the pull bar so you could unlock only from the inside. I just replaced the whole handle lock lever assembly from one I had pulled from the yard. Works flawlessly now.
So my first step was to cut out the shredded portions of the old poly. You can see where the previous owner pulled it back from the top right corner. What you don't see is they gave up on that idea and just cut large slices through it and tried to semi put it back with small pieces of electrical tape. There was not any attempt at actually sealing up the large slices.
So I measured the width and height needed and came up with 40" by 16" square to tape up so I can trace the pattern and circle the door handle and window handle spot.
Using a sharpie I do a rough trace of the pattern including the door handle hole and the window handle post hole.
Now that the pattern is transferred I pulled it off the door and threw it to my garage floor to cut out with my small box knife with snap type blade(s).
All cut out, ready to put up on the door and finalize. Saw an ants nest active so put some raid ant killer in the holes. I will be rid of the ants on the garage door seem if I have anything to say about it.
And this is now all tucked tape up and sealed up to all the same areas and spots as the OEM glue. The top right corner I used some permatex the right stuff to reglue the corner before tuck taping it. Also I did have to do a touch of trimming to both the door handle and the bottom of the door so all panel holes were accessible as well as the new poly sealing up to the old poly still glued on. Before I put the panel back on I put the foam ring back around the window handle post. The door is returned to factory spec.
Now to check over the radio wiring and see if I screwed up a crimp or if I miss wired the battery/ignition wires.
06-12-2019, 05:38 AM
Re: Bringing life back to an abused 92 CDM VX
This will correctly set off the alarm when a door or the trunk is opened and the alarm is set but yeah it's wrong.
