HELP!! Bad Voltage Regulator?

[MPDano]

...the rest of the pics

[bcredliner]

Great!

[Omerta]

I'm getting some surging during idle. When I trace my Voltage vs Time it bounces between 12.8 and 14.3V at about 10 Hz or so.

Its either my voltage regulator or load related. Would the air compressor have enough load to effect the VR if it was cycling? I have no codes and the air system has been working fine.

[omodos]

Originally Posted by e30cabrio

Drove to O'Reilly. Alternator bad.

On the way back the car reported as low as 10.4.

Turned off, not on charger:


Fluke:


Charging, still off:


Fluke is higher which I find really odd:



Called dealer, they are hemming & hawing on the warranty covering this.

Fluke being higher is a relief to me! a while back my digital multimeter was always showing a voltage reading higher than the OBC! I thought it was just me or my voltmeter being wrong, does really beg the question which of the 2 the obc reading or the fluke multimeter readings are true

[Omerta]

Originally Posted by omodos

Fluke being higher is a relief to me! a while back my digital multimeter was always showing a voltage reading higher than the OBC! I thought it was just me or my voltmeter being wrong, does really beg the question which of the 2 the obc reading or the fluke multimeter readings are true

I would trust the fluke. You'd have to study the circuits in detail to determine what potential the OBC is reading or interested in.

[StephenVA]

Question, when you "full Field" the alternator, does it jump to 14V and 150+ amps? When it was bench tested at the shop they select a set of jumper cables to allow a test step to test max alternator output (full Field) as it shorts out circuit to the regulator. In the older none computer adjusted ones you could just cross the terminals.

[Omerta]

"full field" is putting maximum voltage to the commutator via the voltage regulator, with feedback to the VR.

You can't short circuit the VR. You need to inject voltage and amperage to the rotor through it in order to create the EMF to make the 14V/180A (dependant on load). The produced voltage will be dependant on the feedback loop to the VR.

[StephenVA]

Thanks for the corrected info on the Volt regulated system. Having been out of the bench repair world for many years I have not kept up on the proper test steps, especially as most parts have gone to the "vehicle test - Failed?" replace parts and all associated parts nearby, repair process.

[ssx5]

Hello all
I am dealing withe the same tranny fail-safe prog issue. Last weekend I had an Indi mechanic replace all the power steering hoses, reservoir and the front right side axel rod as my CV boot was ripped and leaking grease. Came home after driving 50 miles. Next time when I start driving I see this 'Tranny failsafe prog activated' message and obviously gears shift was rough. went back to the mechanic and he cleared all error codes and was fine for one trip to work before the tranny code came back.
My question is could the mechanic have touched or messed unintensionally with any other part - alternator that would cause this problem? Battery voltage shows 11.5v
Thanks in advance

[upallnight]

Originally Posted by ssx5

Hello all
I am dealing withe the same tranny fail-safe prog issue. Last weekend I had an Indi mechanic replace all the power steering hoses, reservoir and the front right side axel rod as my CV boot was ripped and leaking grease. Came home after driving 50 miles. Next time when I start driving I see this 'Tranny failsafe prog activated' message and obviously gears shift was rough. went back to the mechanic and he cleared all error codes and was fine for one trip to work before the tranny code came back.
My question is could the mechanic have touched or messed unintensionally with any other part - alternator that would cause this problem? Battery voltage shows 11.5v
Thanks in advance

When was the battery last replaced?

You need to bring it back to the mechanic and have him replace the battery. A battery that is only reading 11.5V is basically DEAD.