Flickering / Winking / Blinking Battery Light

[tempaccount]

I have a 2005 Lotus Elise that begun winking or blinking the battery / alternator light during my last track day. The winking (it's not a constant blinking) is very sporadic and seems to come and go.

I was able to capture some of its behavior on video. The battery light is the red light on the left bottom row that stays lit up.

Before I start the engine it seems to blink as some solenoid pulses(maybe the fuel pump?). Then after I start the car the light flickers and then seems to flicker out as the engine revs.

I've also recently experienced the battery light not even coming on when the ignition is keyed, it stays dark for a few miles and then seems to come back when the car is slowed down to idle.

I have checked the battery terminal connections and have charged the battery. I also checked the fuse on R3(Position Alternator Sense) and it's still good. The serpentine belt visually looks good but I remember smelling some burnt rubber aroma from the engine compartment after my first session or two at the track.

[apk919]

Do you have a voltmeter? If so, measure the voltage at the battery while the engine is running... report back.

Oh, BTW, is your car still N/A or aftermarket supercharger?

[tempaccount]

I checked the voltages at the battery. I only have a cheap Radio Shack multi-meter so I don't have a lot of confidence in its accuracy.

Battery voltage (at rest): 12.6
Battery voltage with engine running: 14.3

The car has a Black Watch Supercharger and is currently running a slightly shorter belt 75.08" (75.50" stock), with less than 500 miles on the belt.

[tempaccount]

Originally Posted by TheViper

Typical symptoms of a bad battery or connections.
Cheers, Michael

The battery was replaced 18 months ago with a new Interstate and seems to hold a charge well. I checked the water and all the cells are full without any signs of leakage or boiling. The connections at the battery are clean and tight.

I have investigated the alternator splice for the BWR kit and wiggling the wiring at the splice location doesn't seem to effect the battery light flicker. The loop by the alternator still has slack and as I rev the motor I can't see any pull or flex.

Maybe one of the smaller gauge purple, brown, green alternator wires has come loose?

[apk919]

Originally Posted by tempaccount

I checked the voltages at the battery. I only have a cheap Radio Shack multi-meter so I don't have a lot of confidence in its accuracy.

Battery voltage (at rest): 12.6
Battery voltage with engine running: 14.3

The car has a Black Watch Supercharger and is currently running a slightly shorter belt 75.08" (75.50" stock), with less than 500 miles on the belt.

Voltages are fine.

Originally Posted by tempaccount

The battery was replaced 18 months ago with a new Interstate and seems to hold a charge well. I checked the water and all the cells are full without any signs of leakage or boiling. The connections at the battery are clean and tight.

I have investigated the alternator splice for the BWR kit and wiggling the wiring at the splice location doesn't seem to effect the battery light flicker. The loop by the alternator still has slack and as I rev the motor I can't see any pull or flex.

Maybe one of the smaller gauge purple, brown, green alternator wires has come loose?

I agree with TheViper... sounds like a bad connection or wire somewhere... I've seen similar symptoms after a track day on another BWR S/C car... I think in that case the alternator wire was actually fraying...

[TheViper]

I believe the alternator output is below what it should be. This could be because there is a defect in the alternator or the belt is slipping.
Cheers,
Michael

[apk919]

Originally Posted by TheViper

I believe the alternator output is below what it should be. This could be because there is a defect in the alternator or the belt is slipping.
Cheers,
Michael

I'm only getting 13.9V at the battery while the engine is idling...

[TheViper]

Right in the 13.5V to 14.5V range. I have heard that there are alternator issue with these aftermarket supercharged cars, is this one of them?
Cheers, Michael

Originally Posted by apk919

I'm only getting 13.9V at the battery while the engine is idling...

[tempaccount]

Originally Posted by TheViper

I believe the alternator output is below what it should be. This could be because there is a defect in the alternator or the belt is slipping.
Cheers,
Michael

From this post it looks like voltage is where it should be?

Originally Posted by TheViper

At idle take a voltage reading across the battery, with a correctly operating alternator you will see 13.45V +

I guess if my meter is off by more than 5%... I'll see if I can muster a better meter.

[apk919]

Originally Posted by TheViper

Right in the 13.5V to 14.5V range. I have heard that there are alternator issue with these aftermarket supercharged cars, is this one of them?
Cheers, Michael

I know of two potential problems with aftermarket supercharged cars and their alternators... one is that some aftermarket kits relocate the alternator to a place where it gets very little airflow, leading to overheating and early failure, two is that the replacement cable to the relocated alternator is a bit short, and when the engine torques in its mounts (especially with track usage), the cable is pulled taught and can fail from fatigue.

[TheViper]

Do you have another battery that you can temporarily install to see if the same symptoms prevail?
Cheers, Michael

Originally Posted by tempaccount

From this post it looks like voltage is where it should be?



I guess if my meter is off by more than 5%... I'll see if I can muster a better meter.

[jallingt]

FWIW, I have been experiencing this same issue, but my light does not stay on.... it only flickers a few times then goes away after start up.
No blinking when the car is not running either.
It seems to only happen to me when:
1. The car has not been driven for more than a week, and has not been on a battery tender.
2. The car is cold, after the car warms-up no more flicker.

I have not checked any of my voltages yet. My battery is a repalcement one for the "leaky" OEM, it must be about 4yrs old. After sitting for a few days off a tender sometimes the car will start with a very short crank ~1sec, other times it may take ~4sec.

[tempaccount]

I borrowed a professionally calibrated (and expensive) Fluke meter to rule out an erroneous reading.

The voltage at the battery with the car at idle is reading 14.35 so I think I can rule out a bad alternator, and likely not the belt.

I had also heard about the wiring being stressed with the alternator relocation before I did the install so I was careful to leave a lot of slack...

If there was a bad connection with one of the smaller gauge wires would it give these symptoms? If so which wire should I start with and any suggestions on how to diagnose?

[TheViper]

As you are getting 14.35V at idle, the alternator is operating within parameters. Change the battery and see what happens.

Originally Posted by tempaccount

I borrowed a professionally calibrated (and expensive) Fluke meter to rule out an erroneous reading.

The voltage at the battery with the car at idle is reading 14.35 so I think I can rule out a bad alternator, and likely not the belt.

I had also heard about the wiring being stressed with the alternator relocation before I did the install so I was careful to leave a lot of slack...

If there was a bad connection with one of the smaller gauge wires would it give these symptoms? If so which wire should I start with and any suggestions on how to diagnose?

[jim-clayton]

Shawn's car melted the small wires on the alternator. He has BWR.
I have a new connector with high temp wire if you need it.
My alternator reads 14.1 fwiw.

[glb]

when you measured battery voltages, did you use the battery post or cable clamp? If it was the latter, check @ the post as well, to ensure good connection at clamp.

[GoatOfRafin]

I have the GReddy supercharger installed and had this thing with flashing battery when the cables connecting the alternator to the electrical circuit were cut due to vibrations. Battery light flashes or remains constantly lit when the electrical circuit does not get "fed" by the alternator.

[tempaccount]

Originally Posted by GoatOfRafin

I have the GReddy supercharger installed and had this thing with flashing battery when the cables connecting the alternator to the electrical circuit were cut due to vibrations. Battery light flashes or remains constantly lit when the electrical circuit does not get "fed" by the alternator.

Which alternator connections?

[scottyb]

Have you checked to see if the battery terminals are tight? Weird things can happen when the terminal is loose.

[GoatOfRafin]

Originally Posted by tempaccount

Which alternator connections?

The connections between the alternator and the rest of the electrical circuit.