2007 1165A1 ELECTRIC SYSTEM PROBLEM ON STARTUP ONLY ?

[D Foster]

When first starting the engine, the rpm's pulsate on the engine and electrical system for approx. 1-1 1/2 minutes than goes to normal? When this occurs my headlights, signals , etc. all fluctuate in addition to the engine. After this stops, the engine & electrical system appears to work fine. I initially thought it was a problem with my regulator (Niehoff N3135) and replaced it with another. It continues doing the same thing? Any help would be appreciated. Thanks, Dennis

 

[springer1981]

That is the EESS pulsing the glow plugs. Normal operation for that version of the start box.

 

[D Foster]

That is the EESS pulsing the glow plugs. Normal operation for that version of the start box.

THANK-YOU! I appreciate the quick response. The website is a wonderful thing.

 

[Coonass77]

When first starting the engine, the rpm's pulsate on the engine and electrical system for approx. 1-1 1/2 minutes than goes to normal? When this occurs my headlights, signals , etc. all fluctuate in addition to the engine. After this stops, the engine & electrical system appears to work fine. I initially thought it was a problem with my regulator (Niehoff N3135) and replaced it with another. It continues doing the same thing? Any help would be appreciated. Thanks, Dennis

Out of curiosity, how high does the voltage go on your volt meter while it's pulsing? Into the red? Have you measured the actual voltage?
My M1165 pulses also (as do all these trucks), but mine pulses into the red and I've measured 30'ish volts on the peaks. After the 90 seconds or so, the regulator settles to right where it should be (28'ish volts). I haven't found a clear answer if pulsing into the red is "normal", or if it could be a regulator problem.

 

[Action]

My M1165 pulses also (as do all these trucks), but mine pulses into ....,,,,

Nope. All these trucks do not pulse. It depends on what PCB is in it.

 

[TOBASH]

Mods … we need a sticky identifying the pulsation issue and indicating that it’s normal for several PCB/EESS. It’s a normal part of glow plug activation when the engine is cold.

 

[papakb]

It's commonly referred to as AFTERGLOW. The control box pulses the glow plugs until it starts to see the temperature increasing. This is why it's bit longer in cold weather.

 

[Coonass77]

Nope. All these trucks do not pulse. It depends on what PCB is in it.

Yes, you're correct. I know the newer ones don't pulse. I was referring to the older ones that do.

 

[Coonass77]

Most of the times these forums are extremely helpful. Sometimes these threads go sideways and I'm not sure why.

Yes - I know about afterglow
Yes - I know it's normal
Yes - I know it's temperature dependent
Yes - I know the newer start boxes don't pulse
Yes - I understand the logic and operation of the HMMWV glow plug control system

My question was specifically about how high the voltage normally pulses and if pulsing into the red on the gauge and hitting 30'ish volts was normal. I'm sorry if my question wasn't clear.

For reference: M1165 with 400a alternator and older style (2 connector) KDS EESS

Thanks for any help that anyone can provide.

 

[Retiredwarhorses]

Most of the times these forums are extremely helpful. Sometimes these threads go sideways and I'm not sure why.

Yes - I know about afterglow
Yes - I know it's normal
Yes - I know it's temperature dependent
Yes - I know the newer start boxes don't pulse
Yes - I understand the logic and operation of the HMMWV glow plug control system

My question was specifically about how high the voltage normally pulses and if pulsing into the red on the gauge and hitting 30'ish volts was normal. I'm sorry if my question wasn't clear.

For reference: M1165 with 400a alternator and older style (2 connector) KDS EESS

Thanks for any help that anyone can provide.

It pulses at the same voltage “24v” as what the plugs are rated at…the S3 no Longer pulses, instead it supplies 5VDC for 2mins, this is unreadable on the voltage gauge and has no effect on any other components in the electrical system.

 

[D Foster]

Out of curiosity, how high does the voltage go on your volt meter while it's pulsing? Into the red? Have you measured the actual voltage?
My M1165 pulses also (as do all these trucks), but mine pulses into the red and I've measured 30'ish volts on the peaks. After the 90 seconds or so, the regulator settles to right where it should be (28'ish volts). I haven't found a clear answer if pulsing into the red is "normal", or if it could be a regulator problem.

Hello, Mine does not go into the red at all. Mine pulsates approx. 60-90 seconds and levels out into the green only. While pulsting before leveling out it stays into the green. Mine tends to start off into high yellow for approx. 20 seonds. I can correct this by increasing my RPHs (throttle) but usually don't as it jumps up to green, pretty quick. On yours after going into the red it does settle down in green charge area, right? I have check actual volts but mine seems okay according to the gauge.

 

[Mogman]

Most of the times these forums are extremely helpful. Sometimes these threads go sideways and I'm not sure why.

Yes - I know about afterglow
Yes - I know it's normal
Yes - I know it's temperature dependent
Yes - I know the newer start boxes don't pulse
Yes - I understand the logic and operation of the HMMWV glow plug control system

My question was specifically about how high the voltage normally pulses and if pulsing into the red on the gauge and hitting 30'ish volts was normal. I'm sorry if my question wasn't clear.

For reference: M1165 with 400a alternator and older style (2 connector) KDS EESS

Thanks for any help that anyone can provide.

I would not worry too much about the voltage "overshoot" you are seeing on the voltmeter, I would think that would be pretty much normal.
ALL regulators control on error, that is to say it has to get out of the set voltage for the regulator to react. The higher current the alternator is capable of the larger that error can be.
Unless extraordinary steps are taken because of the sensitivity of the application.

 

[Coug]

to me this does sound like the afterglow function on an earlier start box.
Just because it's a newer truck doesn't mean some schmuck in the motor pool didn't throw in whatever box they had on hand

 

[Mogman]

Hello, Mine does not go into the red at all. Mine pulsates approx. 60-90 seconds and levels out into the green only. While pulsting before leveling out it stays into the green. Mine tends to start off into high yellow for approx. 20 seonds. I can correct this by increasing my RPHs (throttle) but usually don't as it jumps up to green, pretty quick. On yours after going into the red it does settle down in green charge area, right? I have check actual volts but mine seems okay according to the gauge.

This has been said many times, the factory gauges are not very accurate, so indicated readings will be different from one truck to another.
The reason the alternator does not start making power for 20 sec. or so is called soft start.
Increasing the RPM during afterglow will just make the job of the regulator harder, I always let my truck idle until the afterglow has stopped.