darkling

so last night on my way back home from vegas .i stopped to stretch and my car wouldn't start again . got a p1637 and 8 code .
so i towed it home charged the battery last night it's a 12.57 now check voltage to large red terminal on alt 12.52
started car dtc shows 11.2 voltage and service light and codes are back

i checked connections at starter found that my starter bolts where loose
tightened them . didn't feel any loose wires on the solenoid.
fired it up and still 11.2
checked 4 pin connector have 12 v on one red ign off and 10v on other red ign on.
thinking the starter being loose just fried the voltage regulator

GCG

So you charged the battery overnight and using a multimeter you got 12.57v at the battery and 12.52v at the alternator before starting the engine, right? If right after charging the battery all you're getting at the battery post is 12.57v, it seems your battery is not fully charged. I suggest beginning by making sure you fully charge your battery and then take it to an auto parts store to have it load-tested.

When you tightened your starter it was the perfect opportunity to check the connections at the starter solenoid. It is critical that all connections at the starter solenoid are clean and tight.

Turn on the car and with a multimeter read the voltage at the alternator (and verify if the alternator is working as it should) and then at the battery. These voltages should be basically the same, otherwise something is wrong in the alternator-starter-battery chain. If that is the case, check the 2 fusible links between the alternator and the starter.

darkling

k i'll check the link tonight the car starts right up and not having but a .05 drop from battery to alternator drop makes me think the starter connections are good i did try and move them and they where all tight but mind you it was 3am .
yeah there is no voltage change at the alt when running and checking the second red excite wire makes me believe alt

GCG

Check the schematic below. There are 2 fusible links between the starter and the alternator. If they are fine, both of them should have battery voltage on the alternator side with engine off. The L wire brings 10v at a limited current from the PCM into the regulator and this is the signal that excites the alternator.

Just a bit of advice: If you verify that your alternator is bad, don't give it as a core. Plenty of horror stories here. You can replace the regulator. Take a look at this post. It has info on the right regulators for both, 97-01 and 02-04. The price is around $30.

BigGun

What is the voltage at the battery with the motor running? This will tell you if the alternator is charging. Should be about 13.5-14.7. If not check the output at the alternator.

darkling

nope alt is not charging 1 red pin at the alt is hot at 12v with ignition off the other red has no power num 3 left to right
but with key on i have 10v at alt plug red wire number 2
so i work at carquest got a reman bosch tonight but some moron dropped it and cracked case so i get another tomorrow night i'll keep you filled in

Bill Curlee

100%

BC

darkling

k replaced the alt today 13.8 lights and heater on high . gonna be alittle high cause i charged the battery yesterday