Calling Electrical Engineers.

[Logue]

Ok so here it is. I have been getting code 1500 generator terminal FR circuit malfunction. My 3 alt dash warning light flicker on and off intermitantly no pattern. Get dim etc... Battery voltages varies between 11.8-15.5V while on. The battery is holding a good charge. 12.1v-12.4v off. Can anybody make sense of what this says below. I found it in the dsm manual Cd. I just got home from school. I tried to read this but my brain hurts i just went through 8 hours of basic electrical.. Can you guys explian this? I also just found i have a bad connection at the coolant temp sensor. But i was getting the code 1500 before this.


GENERATOR CURRENT CONTROL

During the period the engine is in operation, the
engine ECM achieves duty control of the continuity
between generator terminal G and the ground. (In
this case, the OFF duty of terminal G is controlled
to equal the ON duty of the power transistor in the
voltage regulator.)
Operation of the headlights causes a sudden increase
in current consumption, but the engine ECM
suppresses a sudden increase in the generator output
current, thereby preventing the sudden increases
in electric load from abruptly reducing the
engine speed while the engine is running at idle.
(During the period before the generator generates
enough power, the battery current is additionally
supplied to the headlights, etc.) During the period
of approximately 0.5 seconds after the power steering
pressure switch has been set to ON and also
during the period of approximately 0.5 seconds after
the selector lever has been changed over from the
N range to the D range, the engine ECM controls
generator terminal G in terms of 30% OFF duty
to suppress generation of power by the generator.
L ECM
Engine coolant temperature sensor
Crankshaft position sensor

Air conditioning switch

Power steering pressure switch

Ignition switch-ST

N71EiK61AA
Under the following conditions, however, this control
is not achieved.
l High engine speed
l Engine coolant ternperature 50°C or lower
l Air conditioner swiitch ON
l More than 0.5 seconds after the power steering
pressure switch has been set to ON
o More than 0.5 seconds after the selector lever
has been changed over from “N” to “D”
l Three seconds or less after the engine has been
started
When a high signal at generator terminal FR lasting
for more than 20 seconds is input to the engine
ECM during operation of the engine, the engine
ECM determines that the generator terminal FR
circuit has been open-ciircuited and stores diagnostic
trouble code (No. P1500) in memory, and places
generator terminal G iin the always OFF state.
__________________

 

[ddavisaf]

L ECM
Engine coolant temperature sensor
Crankshaft position sensor

Air conditioning switch

Power steering pressure switch

Ignition switch-ST

N71EiK61AA
Under the following conditions, however, this control
is not achieved.
l High engine speed
l Engine coolant ternperature 50°C or lower
l Air conditioner swiitch ON
l More than 0.5 seconds after the power steering
pressure switch has been set to ON
o More than 0.5 seconds after the selector lever
has been changed over from “N” to “D”
l Three seconds or less after the engine has been
started
When a high signal at generator terminal FR lasting
for more than 20 seconds is input to the engine
ECM during operation of the engine, the engine
ECM determines that the generator terminal FR
circuit has been open-ciircuited and stores diagnostic
trouble code (No. P1500) in memory, and places
generator terminal G iin the always OFF state.
__________________

Here's the important information in that giant post of yours Sorry it took me so long to respond, I had to take a nap about half way through the post.

Anway. It's pretty much saying a couple of things. But I'll try my best to simplify it. A switch or connector went to fritz. Check your:
L ECM

Engine coolant temperature sensor

Crankshaft position sensor

Air conditioning switch

Power steering pressure switch

Ignition switch-ST

The code was throw because one of those switches is stuck in the open position.

 

[Logue]

My coolant temp sensor was unhooked before for the last 2-3days because i was overheating in the heatwave here and needed the fans on all the time. I hooked the CTS back up. Fan comes on at normal time like 212F. the gauge needle on dash jumps around though. I read somewhere that means the coolant temp sensor is bad. But on my logger i'm still getting good reading. Still gets hot but i think it'll be ok.

Crankshaft position switch?? I have a 6 bolt swap. Soo i don't know if the switch is now at the CAS.

I took out the AC so i don't even remember where that switch is. Can anyone refresh my memory on that one.

Power steering pressure switch is good.

I have a HKS turbo timer with the harness in the ingnition switch but i don't think that causing any problems. I'm still getting high voltage reading directly from the alt., battery, and timer. I unhooked the ground to the battery car didn't die while running.

 

[Black95TSIawd]

did you ever end up fixing this issue? This code just came up on my 97 as well.