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Ticking sound from passenger floorboard

7K views 21 replies 7 participants last post by  281lxm 
#1 ·
Hello all,
Sorry I've been gone for a while...too busy in real life. Recently have experienced some issues with my 86 Euro 500SE...rough idle, lights flickering, now battery draining/not charging. Suspecting voltage regulator or at worst alternator. Last night, a new symptom appeared: intermittent, clearly audible ticking noise (like a clock) from passenger side floor board/wheel well that started with car running and persisted with car stopped. Any ideas how/if this correlates?
Thanks all...have a great weekend!
Kali
 
#4 ·
You need to do a draw test. Disconnect the ground cable from the battery and connect a test light between the ground post and the ground cable. Light will light with a draw. remove fuses until the light goes out. When the light goes out you have found the circuit that has the draw. Be sure the deck lid and all doors are closed or you will get a false reading.
Once the circuit is found then trace the items on the circuit.

Do you have an alarm on the car, original? aftermarket? If the clicking is truly coming from the foot well it might be the alarm module, the clicking is the horn / light flasher in the alarm module.
 
#5 ·
i vote alarm module... Disconnect that bad boy, and the tow device in the trunk.
 
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#7 ·
Finally had time to dig into my passenger footwell...not exactly what I was expecting. The ticking sounds seems to emanate from #1 , the idle speed control relay?! 004 545 10 32

I think #2 &3 are seatbelt relay modules. The orange cable #4 was cut and is not in continuity.

Should I just replace the idle speed control? Any input appreciated.
 

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#8 ·
ok how old is your coil?
 
#10 ·
just a longshot, usually misfires, poor performance can be the coil failing. but swapping that relay is simple. just lots of electrical data going thru that box. curious if there is any issues inside the relay. thought for sure it would be the becker alarm. if it is the iscu thats easy, it fixed many issues with mine. o2 sensor too.

would stll ditch that alarm modual....
 
#13 ·
There's nothing mechanical or any movement in the Idle Control Relay to make a noise. Is the the ticking related to rpms?

The alarm module is to the left of your picture. Big black plastic doohickey with two connectors, one larger than the other. Pull both out.


 
#14 ·
Thanks guys but that's what I was saying - my alarm module apparently already had been removed by the prior owner.
I'm not sure but assume that the cut orange cable also has to do with that. I'll look for a new ISCM and will report back.
Thanks for all the input!
 
#15 ·
Orange cable is aftermarket. I do not see an alarm module in your picture. Just for giggles, Unplug your 4 way flasher/Hazard switch and see if the clicking stops. They short out sometimes.
 
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#16 · (Edited)
Idle variations ,uneven running may point to a ignition coil , if all correct then a alternator output current test should be carried out ,the small doiodes in the unit are prone to failure and limit the generated output causing a occasional low battery voltage and at times erratic idling, a bit deceptive as the red warning light still funtions correctly with a partially failed diode!
 
#17 ·
I did replaced the idle speed control unit and the clicking has stopped, although that might be purely coincidental. The hazard system is a good guess, since my left rear blinker does not participate when that is activated - it does work normally otherwise. I don't know off the top of my head what else participates in that but grateful for advice.
I did replace my voltage regulator as well this week and the performance of the alternator has improved. I still have occasional hitch in the idle that goes along with dimming of lights...alternator might definitely be the culprit. I wish this wasn't my daily driver, would make plucking it apart a bit easier!

Thanks all!!
 
#18 ·
the bulbs in the turn signals could be bad or about to go, I had issues with a bad bulb. Glad the click clack stopped with the ISCR (relay) swap. I bet the issue would go away, if the coil got changed out. I have a little issue and when I install a new coil Monday or Tuesday, I will know if it goes away, and let you know. I have others who had some idle issues that the coil r/r fixed. Something about it...
 
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#20 ·
ahh yes that made startups swifter and the slight pulse of idle has gone away. electrical load is much more even as well, no light dims when aux fan comes on with fogs and wipers running. Last is a new O2 sensor as mine is about 110k miles past due
 
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#22 ·
Wowsers, well the relay works if the pumps are running so then Fuel pressure regulator, or the rubber in the CIS needs to be sent out and refreshed. Bad injectors, accumulator ethanol based debris in the CIS.... just spitballing at this point. maybe others will chime in but internet diagnosis may not be good enough. Might be time to see the man at the shop if you cant do the work yourself. Others to chime in I am sure... good luck, keep us up to date.
 
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