[eelsfoot]

Got some feedback with the possible alternator issue....

Pulled codes 622 and 1594. Battery tested good. Charging system read High Voltage (no load 17.66v/128a loaded 17.25v/86.1a). Belts, connections, and grounds look good....

So when the test report "recommends" Regulator Service, what does that mean? doesn't the ECM control the regulator functions?

Do I need to test the Alt or just replace it?

Thanks,

Lance
2001 4.7L Dur.

 

[l1tech]

Obviously the alt is capable of putting out plenty of electricity. The voltage regulating part is in the pcm though and you will need a scanner to test the circuitry. Have you checked the wiring to the alternator to make sure that nothing is grounding out?

 

[Guest]

You may have a bad battery temp sensor in the bottom of the battery tray.

DESCRIPTION
The Battery Temperature Sensor (BTS) is attached
to the battery tray located under the battery.

OPERATION
The BTS is used to determine the battery temperature
and control battery charging rate. This temperature
data, along with data from monitored line
voltage, is used by the PCM to vary the battery
charging rate. System voltage will be higher at colder
temperatures and is gradually reduced at warmer
temperatures.
The PCM sends 5 volts to the sensor and is
grounded through the sensor return line. As temperature
increases, resistance in the sensor decreases
and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain
faults and OBD II monitors are either enabled
or disabled, depending upon BTS input (for example,
disable purge and enable Leak Detection Pump
(LDP) and O2 sensor heater tests). Most OBD II
monitors are disabled below 20 degrees F.

 

[eelsfoot]

BTS....never would have thought of that. All wiring for the Alt is good. I unhooked the BTS and drove up to the store....no sensors in stock, but it will be in after lunch. The charging gauge, after a couple minutes of driving, settled back to normal. Only cycled up to High Charge once, then quickly went back to normal. So maybe the BTS is the culprit....hope so.

Thanks guys....appreciate all the inputs.

 

[eelsfoot]

BINGO!! Bad BTS....thanks bwdakrt. Always enjoy learning something new!!!!

CHEERS.

Lance-

 

[l1tech]

That's a new one on me...hope it's not a short lived cure.

 

[Guest]

BINGO!! Bad BTS....thanks bwdakrt. Always enjoy learning something new!!!!

CHEERS.

Lance-

No problem! Good luck. :mullet:

 

[brad81987]

Where did you find a new BTS?

Thanks

 

[eelsfoot]

AutoZone....

 

[Duner]

You may have a bad battery temp sensor in the bottom of the battery tray.

DESCRIPTION
The Battery Temperature Sensor (BTS) is attached
to the battery tray located under the battery.

OPERATION
The BTS is used to determine the battery temperature
and control battery charging rate. This temperature
data, along with data from monitored line
voltage, is used by the PCM to vary the battery
charging rate. System voltage will be higher at colder
temperatures and is gradually reduced at warmer
temperatures.
The PCM sends 5 volts to the sensor and is
grounded through the sensor return line. As temperature
increases, resistance in the sensor decreases
and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain
faults and OBD II monitors are either enabled
or disabled, depending upon BTS input (for example,
disable purge and enable Leak Detection Pump
(LDP) and O2 sensor heater tests). Most OBD II
monitors are disabled below 20 degrees F.

Good Call!

 

[ThisOldDak]

wow, I didn't know those even existed eheh

 

[brad81987]

Yup, allows the charging system to compensate for temperature affects on the battery. There's a lot of other crazy little things that ECM computer does if you read through the service manual, a lot more than just firing the fuel injectors (and spark plugs in case of the 4.7).

 

[dave2003]

You may have a bad battery temp sensor in the bottom of the battery tray.

DESCRIPTION
The Battery Temperature Sensor (BTS) is attached
to the battery tray located under the battery.

OPERATION
The BTS is used to determine the battery temperature
and control battery charging rate. This temperature
data, along with data from monitored line
voltage, is used by the PCM to vary the battery
charging rate. System voltage will be higher at colder
temperatures and is gradually reduced at warmer
temperatures.
The PCM sends 5 volts to the sensor and is
grounded through the sensor return line. As temperature
increases, resistance in the sensor decreases
and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain
faults and OBD II monitors are either enabled
or disabled, depending upon BTS input (for example,
disable purge and enable Leak Detection Pump
(LDP) and O2 sensor heater tests). Most OBD II
monitors are disabled below 20 degrees F.

Sweet. i was having an issue with my battery guage pegging all the way over to 18v...stumbled across this with a search, replaced my BTS, and no more problems...thank you bwdakrt.

 

[dave2003]

The replacement sensor lasted nearly 9 years. I just ordered a new one. I have been experiencing the voltage gauge pegging at 18 volts the last couple of days.

 

[deadman4u2c2]

BINGO!! Bad BTS....thanks bwdakrt. Always enjoy learning something new!!!!

CHEERS.

Lance-

Would a bad bts make the alternator not charge at all