Having some electrical problems

Grey_Ghost

Leaving Skid Marks
Lifetime Member
Location
Australia (Duh?)
First Name
Gav
Drive
1997 Trigger PFL Manual Legnum.
Hey all.

I'm having gremlins after the alternator went from battery voltage to 22v.

Instrument cluster went from Star Wars to Jedi mode. No needles or backlights. Has some idiot lights.

Climate control fan only works above medium. Rest still works, air con cold, heater hot.

Car hunts any time it's not stationary.

Idles high frequently.

The rest is just blown bulbs and radio.
 

AKKO

2 AYC Bars
Lifetime Member
Location
WA
First Name
Chris
Drive
1998 Galant VR4 Type-V (Facelift)
Fried ECU or what codes does it throw if you can pull them?
 

Grey_Ghost

Leaving Skid Marks
Lifetime Member
Location
Australia (Duh?)
First Name
Gav
Drive
1997 Trigger PFL Manual Legnum.
No codes stored, can't use evoscan to see if it generates anything at the moment. (Laptop problems, not car)
 

whats_doing

QLD Events Manager
Location
QLD
First Name
Sam
Drive
98 PFL Black Legnum - SOLD
MY15 Hyosung GT650R
If you are still running the multimeter in your map light, stop. Put bulb back in. Try replacing every fuse in the cabin. High idle is most likely a boost leak.
Running 22v could also have buggered your ecu.
 

pretzil

2 AYC Bars
Location
Qld
First Name
Rick
Drive
Legnum VR4
Hi, thread revival.
What caused your car to run 22V? Buggered alternator?
What did you do to fix it?

I just started getting a battery light, checked and I have 17V at idle... No blown bulbs yet that I know of.
 

Kaldek

2 AYC Bars
Premium Member
Location
Melbourne
First Name
Ed
Drive
2000 Legnum VR4 Manual, Ford Territory family runabout, BMW K1300R.
Do not run car if it is overvolting. You will cook stuff.

Replace alternator immediately.
 

Kaldek

2 AYC Bars
Premium Member
Location
Melbourne
First Name
Ed
Drive
2000 Legnum VR4 Manual, Ford Territory family runabout, BMW K1300R.
17 volts is high, but 22 volts as mentioned above is really bad. You can fry your ECU.
 

pretzil

2 AYC Bars
Location
Qld
First Name
Rick
Drive
Legnum VR4
Cut the alternator belt and tried to drive home.
Unfortunately I only have a small battery and only made it 20mins of a 25min trip.

Getting a 2nd hand alternator tomorrow. Who knows how long it will last though.
 

pretzil

2 AYC Bars
Location
Qld
First Name
Rick
Drive
Legnum VR4
Alternator replaced with a 2nd hand one and all working good, no sign of fried electrics.
Going to rebuild the old in preparation for the next failure.
 

Xoxide

Leaving Skid Marks
Location
SA - North East
First Name
Reece
Drive
'98 Legnum
Unfortunately I only have a small battery and only made it 20mins of a 25min trip..

Owch. I managed 3 and a half days off my Optima before realising the warning light wasn't just a loose wire and my alt had completely given up the ghost
Major gremlins though.
 

Size1

Leaving Skid Marks
Location
N.S.W
First Name
Simon
Drive
00 legnum vr4
Hi guys. I need some help. Changed my alternator yesterday but unfortunately the new one isnt suitable because it is 3 pin and old one is 4 pin. Thought i would give it a go anyway as i really needed the car for today. Big mistake. Anyway when i started the car the air con came on as usual after disconnecting the battery and oversped. Then the fan stopped and i could smell melted plastic. Has anyone had something similar happen to them and any tips on how to diagnose what burnt out. Really embarrassed by my stupidity so no smart ass comments please.
 

naughtika

OzVR4 Stalker
Location
Brisbane, QLD
First Name
Christian
Drive
'96 Galant VR4, '17 MB A180, '25 Macan GTS
unfortunately no easy way of doing things, but to look and find out if where the smell is coming from.

is it from the engine bay or cabin?

worse case, you may need to remove the whole dash and replace the wire that's in it,

also you'd be glad to know that most of them have connectors, so you can unplug the old one then replace with a better unit.
 

Size1

Leaving Skid Marks
Location
N.S.W
First Name
Simon
Drive
00 legnum vr4
This is what happens when you work in the dark with just a work light. Replacement alternator was the same just had a broken pin. Got my one reconditioned and swapped it out today. My greatest fears were realized, i have fried something. I havent checked the fuses and relays yet but i suspect something more serious hence my previous post. Symptoms so far are
  • No heater/ aircon fan.
  • No central locking.
  • Alternator although completely reconditioned wont charge battery.
Maybe these are supplied on the same wiring loom. Dont know but i certainly am fed up and dont have the patience right now so i am thinking maybe i will bite the bullet and get an auto electrician.
 

Size1

Leaving Skid Marks
Location
N.S.W
First Name
Simon
Drive
00 legnum vr4
Ok. I have found some burnt out fuses that i replaced and this solved 2 problems. Central locking is working again and battery is charging. The air con fan i suspect is burnt out but i can deal with that later.
However the battery light now stays on all the time. I checked the voltage at the battery with a multimeter and i get 15.6 volts. When i had the alternator refurbished the guys installed a new voltage regulator. Is there another electrical component that could be faulty that would cause this? Also can driving the car running higher than normal voltage cause me any other problems?
 

Kaldek

2 AYC Bars
Premium Member
Location
Melbourne
First Name
Ed
Drive
2000 Legnum VR4 Manual, Ford Territory family runabout, BMW K1300R.
Regulation is controlled by the ECU. It is a Pulse Width Modulated (PWM) signal from the ECU to the alternator regulator circuit. The ECU reads the voltage it sees on its power feed lines, and based on what it sees it will send a PWM signal to the alternator to increase or decrease the power it generates. I believe that the "G" wire to the alternator controls the field and the "FR" wire monitors the generation of the alternator.

If you have EvoScan I'd be interested to see what voltage the ECU thinks it's getting. If it sees 13 volts when it's actually getting 14 volts, it will send the wrong signal to the alternator. In your case you would check to see if the ECU is also seeing 15.6 volts. This is a quick test to at least check if your ECU is causing the problem, versus the sparky putting in the wrong part when he reconditioned the alternator.

If you don't have EvoScan, you could just probe the ECU power pin. It's pin 25 on the first (passenger side) plug.

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Size1

Leaving Skid Marks
Location
N.S.W
First Name
Simon
Drive
00 legnum vr4
Thanks Kaldek. I drove the car to work today and no battery light on the dash so i am hoping the ECU has learnt the new alternator and is now regulating the power accordingly. I dont know if this is a plausible explanation either as I havent checked the voltage today because i am very tired but i will check again hopefully tomorrow arvo. I dont have evoscan either but i will probe the ECU pin just to check. The major concern i have is that i could have fried the ECU. BTW for reference i had burnt out the 120amp fuse. Do you have any tips on diagnosing if the aircon/heater fan is burnt out. I havent pulled it out yet so it may be really obvious if it is gone but if it isnt i would like to know what to look for?
 
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