EFI or ECU relay clicking while rig is off??? (2 Viewers)

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antss

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My 00 LX just got a new battery last week and this evening while walking by I noticed a clicking from under the front drivers fender. I tracked it down to a clicking EFI 0r ECU relay located in the box directly behind the battery. (same relay)

Any ides on the cause of this???

Remedies???

Thanks.............Dave
 
antss said:
My 00 LX just got a new battery last week and this evening while walking by I noticed a clicking from under the front drivers fender. I tracked it down to a clicking EFI 0r ECU relay located in the box directly behind the battery. (same relay)
Click to expand...

When the new battery was connected, a voltage surge could of damaged the relay, especially if the ignition key was in the "on" position when the battery was connected. The factory service manual (FSM) gives the following test procedure for the relay using an ohm meter. Remove the relay. There should be continuity between terminal 1 & 3 and no continuity between 2 & 4. When a 12 volt battery is connected to terminals 1 & 3, there should be continuity between terminals 2 & 4. Or, buy a new relay and see if the clicking stops. Or, drive to one of the chain auto parts stores and have them check for diagnostic trouble codes (the scan is usually free). Is that relay marked ECD instead of ECU?
 
Yes, my mmistake , the cover on the box in the bay says EFI or ECD. The relay itself says ECD MAIN RELAY
Toyota 12 v
 
Ever come up with a solution?

My truck is doing the same thing.
 
For the cost of a new relay I might just replace it with a new one from cruiserdan and see what happens.
 
New relays aren't cheap. I tried a knock off one from pep boys and I'm having the same issue, so it's not the relay.
 
Typically, if you have a relay that is chattering, while the power is switched off, you either have a short on the power side, if the relay's coil is directly grounded or a short to ground if power is always applied and the ground to the coil is switched. I do not have my wiring diagram to review for this but I would think that you are looking for a short.

Check to see if power is continuously applied to the coil of the relay.

If so, it probably is a switched ground and you need to trace the circuit to its ground. You may have a frayed wire, or something similar.

If you do not have continuous 12VDC to the coil, you may have a short that is powering the relay intermittently.

Remember, the coil requires current (flow of electricity from battery to ground) for the contacts to close.

Hope this helps,

Jonathan.
 
Thanks LCHardriver, I know this is an old thread, but I figured I would post my solution incase anyone was having a similar problem.

There was a short caused by moisture in the passenger side A pillar from a shoddy windshield install job.

I got a new windshield and I no longer have an issue.
 
Nautilus - Just want to let you know, taking the time to post the resolution was a lifesaver. I have a '99 LX470 with 260K. Been an awesome truck. We've had torrential rain today and my wife pulled into the driveway and said that there was an electrical problem with the truck, the steering wheel / seat memory wasn't working. Then I heard a noise from under the hood and the EFI / ECD relay was chattering. Googled for LX470 EFI chattering and found this thread pretty quickly. Opened the passenger door and the floor was soaked. I have a rust spot on the upper line of the windshield that has been getting worse. Apparently the leak is pretty bad so I am going to have to get it checked out. I vacuumed the carpet and pulled the panel and dried everything in the upper right corner and pulled the connections and blew them all out with an air gun and all is back to normal. I shoved a shammy cloth up in there for the time being as my wife was headed out for the weekend.
 
I had this happen once. I disconnected the battery overnight, re-connected it the morning...... and its never happened again...knock on wood
 
I had this happen once after driving home through a torrential downpour.. truck was out in the rain all day before that. Something didn't like the moisture obviously.. but after a night in the garage it was fine, and it's never done it again.
 
superjuice said:
I've been having the chattering EFI relay for few months now, rain or shine. Seems to have a mind of its own really. I've been leaving the key in the ignition but that's not the answer. Any other ideas/fixes?

Maybe the ignition cylinder? EFI Relay, ignition clicking/dead battery solution!!! - Lexus IS Forum
Click to expand...

nakman said:
I had this happen once after driving home through a torrential downpour.. truck was out in the rain all day before that. Something didn't like the moisture obviously.. but after a night in the garage it was fine, and it's never done it again.
Click to expand...

Same prob. with my 100. Accidentally left the sunroof open with the sunblock slider closed so rain gets directed to the A-pillars. Duhh...
 
Just thought I’d update this. We moved and the new (still outdoor) parking spot is on an incline, haven’t had a problem since parking with the nose up. Maybe something is draining better and whatever it was has dried out.
 
I just had this happen today. Efi relay was clicking after key was out. Starts up fine and clicking stops but I noticed my power antenna was up but my stereo had no power. After trying to lower and raise power antenna I checked my fuse box and found my radio fuse blown. The power antenna was jammed and after changing fuse and reinserting the antenna, the clicking from the efi relay stopped.

I'm thinking maybe water in pillar/ antenna causing a short which blew radio fuse and then causing a load to efi relay? I'll check my wiring diagram and monitor it for a while but hope this helps someone else with the same problem I had.
 
Add me to the club. ‘99 Cdn spec LX470. Has been reliably starting in the cold (-30C) weather we have had lately until yesterday when it was stone dead. Boosted it today and after driving it around for a while the battery recharged but when I took the key out if the ignition… clicky clicky. Traced it back to the IGN relay so the fuse is out for now until I troubleshoot it. This thread is my first stop.

I can’t imagine it being moisture related in my case since it has been cold and dry here for weeks.
 
Last edited:
Another victim.
I have just encountered this on my 2000 100 with 209k on the clock. Drove 3+ hours yesterday. Some very light and sporadic rain showers. Super humid and hot day. Shut it down in the garage and this morning I walk out into my steaming hot garage to hear the clicking. (Another very humid day.)
Let me add, after reading the link above, when we started the truck before the trip, it would not allow me to lock the doors with the truck running. It resolved itself after we stopped and got gas. It seems that the two could very possibly be related.
I pulled the relay and have disconnected the battery until I have time to dig into it and search for the demon.
I plan to hoik everything back up and play with the ignition switch a litle to determine if that could be the issue.
I will post up what I find.
 
Last edited:
Update.
With the expectation to trouble shoot this morning, I put my key in the ignition and jiggled it around and sprayed compressed air in and around the ignition, plugged the relay back in and reconnected the battery.
Drove the truck, parked and shut it off multiple times with no duplication.
I intend on buying the suspect ignition part to have it on hand but right now the gremlin has left the building.

7/7 - I spoke too soon. It is back.
I ordered a new ignition switch ($50).
They are all over the net for anywhere from $17 to $170. I hope I am getting a genuine part. I purchased from a highly rated Flea-bay seller claiming their part is genuine. :meh:
 
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I got my switch late today. Will tackle the repair in tomorrow's heat.
Here is a very good video on the disassembly of the lower dash and getting to the ignition. This is for the replacement of the ignition lock bar or ignition lock but will be a big help if you need to replace the switch.



The switch part number for is 84450-12200 for many years and used in many different Yotas.
 
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