Alternator Died

Early September 2003

What are the symptoms? What may go wrong?

The 1st indication of alternator failure is the battery symbol warning light on the right side of the combination meter (dashboard meter).

2nd indication is the voltage reading (if a volt meter is included [or installed]). If the voltage reads either too high or lower than normal then it is faulty.

3rd indication is other lights turn on, like this: -

Notice the battery symbol light on the right, catalytic light on the left and reverse light??? on the left also. The voltage is 12v to be exact, it is counter compared with a DMM.

To exaggerate the lights: -

A funny thing - the catalytic convertor's heat / temperature (2nd exhaust) sensor is not installed. How come there is a light? What does it have anything to do with the alternator? The sensor was momentarily plug back, but there was no change on the light.

So, how did this all start? For this case, it all started after the car was sent to have an engine wash. :( what a bad move :(

No, next time the washer will be told to wind blast everything more thoroughly. the distributor and AFM was covered with plastic bags. The spark plugs was covered by the original spark plugs cover. Therefore the car managed to start immediately after wash. No problems here.

The alternator did not die immediately after the wash. In fact it died around 50 km away from the washing station :(

It was found out  when suddenly the catalytic and reverse lights were on. Voltage at that time shoot through the roof. Well nearly anyway. It went up to the 2nd line below 18v, which is 16v+, confirmed by the DMM.

In the panic, the ECU was worried to be fried :( so the head lights were turned on in broad day light. It reduce the voltage to around 14v. The car was stopped quickly on a safe side of the road and engine shut down.

Restart the engine and all seems fine for the moment. Therefore continue the journey home which is around 200km. Not too far away the voltage shoots up high again. This time actually touching or exceeding 18v. The head lights were on, the high beam were on, the air-cond at full blast, in all hope to reduce the voltage not to fry the ECU.

Half way home and it rained. The wiper was also on full blast and helps reduce the voltage somewhat. At one point the wiper stopped :( Oh my god, why is this all happening at the same time??? Luckily an emergency stop space was available around 10 km away, so there it goes. 

Once reach, the car is stopped, the bonnet open to check for open fuse. The DMM was called to the service again. Unfortunately no fuse was found to be open. All in order. So, what went wrong??? loose connections may be. So look again and to my surprise one ground was not secured which have 4 wires in total. So nuts and bolts if went and it is grounded :)

Start the car and the wipers came on on-line :) The brother lights is still on, alternator did not recover as hoped. Oh well, continue with the journey.

The voltage kept relatively low around 14v+ when traveling at speed around 100. Once 120 is exceeded the voltage goes to around 16v+.

At low speed 100 it would stay at 14v+ around 70% of the time while some times going to 16v+ and the occasional 17v+. At speed above 120 it would stay at 16v+ around 70% of the time, while dropping down to 14v+ some times and the occasional 17v+.

Once reach home town, my mechanic (Ah Leong 012-6516869) was visited immediately. A simple look and he confirm a dead alternator. During checking he unplug the battery cable while the car is idling. The voltage shoots through 18v and we shut the car down immediately.

The funny thing is..................on the next start up, there was no more problems. The battery symbol light, catalytic light and reverse light did not turn on. The voltage reads 14v :). It was hoped that the momentarily lift of the battery from the alternator might have reset it??? but once home is reach, all the lights came on again :( A heavy burned electronic smell was noted right after shutting the car down :(

Another trip out was required, to collect a alternator I lean to a friend. Along the way everything is fine. Perfectly normal. The heavy burned electronic smell is still around. However when coming home is the saddest part. The alternator completed died. No over charging anymore. The DMM only reads 12v and dropping fast as the head lights was turned on. Therefore most of the journey the head lights were off :( wow, so dangerous :( 

Next morning went to the workshop and replace the alternator. It is learned / guessed that the IC regulator is dead, not the complete unit. Perhaps next time I would not change the whole alternator, but the IC only.



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