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Is it just me or do others also see a grounding issue with either the alternator or the engine?
Thats kinda what I was thinking. According to your tests, the alternator should be charging. Your L circuit is what tells it to charge.

A simple test you can do is compare battery voltage terminal to terminal, vs battery positive terminal to engine body. You should see less than .2v difference. If your numbers dont make sense or are way off, you have a engine grounding problem.

Another test you can do is grab a jumper cable, and simply connect it from the alternator body, to the battery negative terminal, then check your charging voltage.
 

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Discussion Starter · #42 · (Edited)
I just tested the voltage between the following:

Battery positive terminal and battery negative terminal
Battery positive terminal and engine
Battery positive terminal and alternator


All results matched, so the problem can't be bad grounding.

Does anyone know what else could be the problem?
 

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Discussion Starter · #43 ·
I note the following from the test results...

Alternator terminals (grounded to engine/grounded to battery negative post):

IG: Nil/6.2 volts
S: 3 volts/3 volts
L: Nil/6.4 volts
M: Nil/6 volts


The terminals didn't return a result when they when grounded to the engine but they did return a result when grounded to the battery, yet the ground test confirmed the engine is grounded, so the results are conflicting. Is there something I am not understanding?
 

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Discussion Starter · #45 · (Edited)
I think I may have found a clue. S should be 12 volts, have a look at S in the charging system circuit diagram.


Now have a look at my test results of the alternator connector.

IG: 11.5 volts/11.52 volts
S: 4.58 volts/4.58 volts
L: 11.49 volts/11.5 volts
FR: 11.81 volts/11.82 volts

S isn't even hitting 6 volts, so there is resistance either in the wiring or the fuse. Does anyone know if this is of significance?
 

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Yes, you are correct. check fuse 19, and 37

Edit: However, that looks to just be a reference circuit. It may not make a difference because it appears that, as stated before, the alternator is being commanded to charge anyways. So check the fuses, replace if needed. You should see battery voltage on S, but even if you do, and you still have no charging voltage, it'll be time to take it off and have the alternator itself tested.
 

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Discussion Starter · #47 · (Edited)
So the diagrams in the shop manual for the alternator terminals and the alternator connector are pretty crap and I thought the diagrams were of the alternator terminals but they are actually of the terminals in the alternator connector. I realised when the result I was getting on the multimeter from S at the under-hood fuse box wasn't corresponding with the result I got yesterday from S on the alternator connector. These are the correct test results from yesterday of the alternator terminals and alternator connector.

Alternator terminals (grounded to engine/grounded to battery negative post):

L: Nil/6.2 volts
FR: 3 volts/3 volts
IG: Nil/6.4 volts
S: Nil/6 volts


Alternator connector (grounded to engine/grounded to battery negative post):

L: 11.5/11.52 volts
FR: 4.58 volts/4.58 volts
IG: 11.49/11.5 volts
S: 11.81/11.82 volts


I don't know if the FR circuit to the ECU is 12 volts, but if it is then there appears to be a problem somewhere in the FR circuit.

To rule out the FR terminal in the alternator connector being bad, I followed it's WHT/RED wire to it's socket at the top right hand side of the engine bay, disconnected the connector that connects to the socket and then tested the FR terminal inside the connector.

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These are the results:

FR at alternator connector: 4.55 volts
FR at top right hand side engine bay connector: 4.94 volts


What do others think?

Also, could someone please check their alternator connector FR terminal to see what voltage it gets? This will help by confirming if the FR circuit should be running at 12 volts.

29339
 

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Discussion Starter · #49 ·
Yes mate, the alternator is fucked. I took it out today as well as my battery which is now on the charger as I drained it from all the testing. The place where I got the alternator from is going to send out another one to me. I'll report back the outcome after I drop it in.

I bet the remanufactured alternator I got has been stuffed with parts off AliExpress! It lasted just half an hour before shitting itself. Now I'm concerned about the alternator coming.
 

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Now you have experienced my story lol

You'll spend hours making sure you didnt misdiagnose, only to find out its not you, but garbage parts from your supplier.

Honestly, i would just get your money back and go buy one from napa.

RAY 2138346
or if you want OE denso DEN 2100220
 

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Discussion Starter · #51 ·
Sorry for the late response. My internet speed was shaped to 128kbps and this site was timing out as it's Javascript code is crap.

I am going to try the replacement unit and if there is a problem with that then I am going to return it for a wrecked unit. :)
 

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Discussion Starter · #52 · (Edited)
OMFG lol

So I received my replacement alternator today. It isn't a Remy and looks much higher quality. The replacement is the one on the left, the Remy on the right.

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Like the Remy, the protector and harness bracket were missing so I transferred the protector and harness bracket over but when transferring the protector over I sheered off one of the fuckin non-replaceable bolts. It wasn't my fault because the fuckin retard that remanufactured it used mounting bolts that aren't OEM equivalent as the threads stop before reaching the head. This resulted in the protector being lose, and I thought I hadn't tightened it enough (there are no torque specs) so I kept tightening it to the point where two teeth in my brand new ratchet stripped and then the fuckin bolt sheered off!

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What's more, the retard that remanufactured it didn't use the same bolts!

29348



Here's an overview of what happened.

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The protector is holding with two bolts only but it should be fine.

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Tomorrow I will install the alternator.
 

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Discussion Starter · #54 ·
This is fucked. The problem still persists with the replacement alternator. The first time I started the car the battery charge light flickered on and off for a bit and now it just stays on. What the fuck?! Seriously!! Now I want to get rid of the car it can fuck off.

The problem is something not on paper. Is it possible over tightening the drive belt could do this? It's a new belt. Perhaps it worked for a few seconds at the start until it's liners shredded or something. The last replacement alternator worked for the first half an hour before it stopped working and while it was working the drive belt was squealing and then stopped squealing once the alternator stopped working.

Also, test the air conditioner compressor. It span so freely it wouldn't stop, I thought it was magic, so I am certain that is not causing the problem.

I so want to have this car scrapped but I must know what the fuck is causing this problem!
 

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Discussion Starter · #56 · (Edited)
Nah I didn't try it because I was able to confirm that there isn't a grounding issue.

I am now certain the problem is not the alternator.

You know, when I tested all the circuits there was a voltage loss of ~0.5 volts in the FR circuit between the engine wire harness alternator connector and the node that it connects to.

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FR circuit was 4.58 volts at the engine wire harness alternator connector and 4.9x volts at the node. There is nothing in the manual that indicates what the voltage should be but I have read online that it's a 5 volt circuit.
The reason for this voltage loss is likely because I have catastrophic valve cover gasket failure and oil goes everywhere and has soaked the engine wire harness at the junction where the wires meet before going to the engine wire harness alternator connector. I took this photo of it 45 minutes ago before spraying it with WD-40.

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I don't know what the significance of a ~0.5 volt loss in the FR circuit would be.
It's dark here now so I'll let the WD-40 break down the oil overnight and then tomorrow I'll rinse it down with hot water and see if it's made a difference.

OMG, so I just went outside for a moment to check something and while I was at it I closed my bonnet and turned on my engine to put up my window and the battery warning light wasn't on! I then revved the car and it came on but then it went off once the rev's came back down. I then revved again but this time the battery charge light stayed on.
The interior light was dimming when this was happening. I think the WD-40 is doing it's work and the problem is the wiring! The ECU tells this alternator when to charge, and that happens through FR circuit! Haha I think I may have solved this problem!!! We will wait and see but I can't help smiling! :)
 

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Discussion Starter · #57 · (Edited)
Now that I think more about it, a ~0.5 volt loss and the oil soaked engine wire harness is an in-your-face sign that the computer signal may not be properly received by the alternator; that wire is carrying a digital signal.

I'm wondering though, how would oil get into the wiring? Could it even get into the wiring? Wire is coated and I imagine it would be resistant to oil.
 

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Discussion Starter · #58 ·
I have just done even more thinking... if the battery charge light is coming on and going off without me changing the alternator belt tension, then the problem can't be related to the belt tension.
 

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If the alternator is spinning, its not your belt.

An oil soaked harness/alternator can cause resistance, but im not convinced the harness is your issue.

Even though you can see good voltage, you can have a circumstance where the connection is still bad under load. Id do the jumper cable test anyways.

You need to watch your voltage as you are revving the engine. I suspect you are running off the battery and you simply drained it to the point where the light stays on.

If you think the harness is the issue, you can run a jumper wire on that circuit parallel to the FR circuit wire giving a clean path using wire probes like these

https://www.amazon.com/Piercing-Aut...cphy=9010673&hvtargid=pla-1147848815678&psc=1
 

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Discussion Starter · #60 · (Edited)
I haven't done the jumper test because I am not getting good voltage from B terminal. The jumper test will make the battery charge light go off but it won't help B terminal.

The alternator can spin without putting out current if the alternator rectifier doesn't receive the signal from the computer to do so.

Battery is fine. I just fully charged it with a battery charger, again. :)

Yes, a jumper-wire-like test is on the cards next if cleaning the oil soaked engine wire harness doesn't fix the problem. Thanks for the link.

I'll have the answer in two hours from now.
 
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