Idiot light – A/T & BATT flashing!!!!

[monnomania]

Small problem today while driving the hills of North Carolina’s Great Smoky Mountain National Park.

Vehicle: L400 V6 3L Gasser, Long wheel base, 4” lift with 32” tires (265/75 R16 = 5% out according to my gps tracking) Auto transmission MODERATE/Heavy load (camping gear)

Symptom: Accelerating under load while climbing steep hill, approx 40kph RPM between 2000 and 2500 the BATT AND A/T idiot lights flash at the same time (same circuit?) intermittent and random moments
1- OD off or on no difference
2- PWR setting on trans makes moderate improvement, but lights still flash

Once the speed/RPM pass these marks the lights do not flash again. It MIGHT have a connection to the gear changing of the transmission but I have not been able to determine the flashing with feeling the trans shifting.

WEIRD: flashing is worsened when making a left curve. I also think that the flashing has caused some sort of power surge that burns out the 25A fuse connected to the aftermarket (not me the Japanese guy before me!) bumper mounted driving lights.

Anyone got any clues?

[thedjjack]

My guess would be alternator trouble starting....I would reduce your use of power inside the van (you might be pulling more amps then the alternator is putting out)...

Check battery connections
if you have a volt gauge look at what the alternator is putting out...Charging should be 13.5 volts or better....

good luck

[monnomania]

Thanks all.

Even though the alternator rebuilder guy decided the alternator was good - putting out 14.1 v during tests I decided to replace the alternator. And as you guessed it, that solved the problem.

Thanks again
Chris