Alt not charging

[vertsilvia93]

Originally Posted by greenwood

you need to have a wire running to that light on your dash. Or you can wire in a resist to make the alternator is hooked up to the dash light. It is a silly thing, but I'm pretty positive this will fix your issue. do searches to read more.

the little light is a form of resistor that lets the alternator know to start charging. without it no dice on charging anything.

how or where could I find out how to do this?

[greenwood]

Originally Posted by vertsilvia93

how or where could I find out how to do this?

Sorry man, I posted that 8 years ago when I had a similar issue when I rb20 swapped my s13. You have to do some wire tracing or digging on the internet about the issue.

If you are going to tune/fix/tinker on these cars you have to use the wealth of knowledge already available. Guy mentions the charging dash light here as well. I found that info within a 10 second google search.

https://zilvia.net/f/showthread.php?t=634905

[greenwood]

Also if your intimidated by using a multimeter, dont be just watch youtubes on it and get one from harbor freight for 6 bucks they are cheap and work well.

[vertsilvia93]

Originally Posted by greenwood

Also if your intimidated by using a multimeter, dont be just watch youtubes on it and get one from harbor freight for 6 bucks they are cheap and work well.

trust me I have done hours and hours of research. I have a multimeter. The battery light on the dash is the exciter for the alternator. The light does not turn on when the key is on the on position. i am going to just run a wire directly from the alternator to the back of the gauge cluster. There might be a break in the wire.

[brndck]

Originally Posted by vertsilvia93

trust me I have done hours and hours of research. I have a multimeter. The battery light on the dash is the exciter for the alternator. The light does not turn on when the key is on the on position. i am going to just run a wire directly from the alternator to the back of the gauge cluster. There might be a break in the wire.

so to take this conversation in a slightly different, but hopefully useful direction, when I ditched my stock cluster for a STACK cluster, my alternator would not charge upon starting up the vehicle. BUT, once I rev the engine to about 3-4k, it would kick on and begin charging. The stack cluster doesn't use any of the factory wiring, so the connectors for the factory cluster are just unplugged and left hanging.

long story short, the exciter from the cluster is NOT the only way to trigger the alternator. (I've had this stack cluster on 3 s13s now, same result on all 3 cars)

[vertsilvia93]

Originally Posted by brndck

so to take this conversation in a slightly different, but hopefully useful direction, when I ditched my stock cluster for a STACK cluster, my alternator would not charge upon starting up the vehicle. BUT, once I rev the engine to about 3-4k, it would kick on and begin charging. The stack cluster doesn't use any of the factory wiring, so the connectors for the factory cluster are just unplugged and left hanging.

long story short, the exciter from the cluster is NOT the only way to trigger the alternator. (I've had this stack cluster on 3 s13s now, same result on all 3 cars)

HMMM this is new to me. So you've been running that stack cluster and the wire that runs from the alternator to the stock cluster is connected to nothing?

[brndck]

correct. my stack cluster does have a voltmeter built in, and you can monitor battery voltage. when you first fire up the car it will just sit static around 11.5-12v, and slowly you can watch it trickle down (takes a while, its not immediate), but if you free rev the engine (just once, above 3-4k, then let it sit back at idle), you can see the alternator kick on and start producing 13-14v.

I'm curious to see what anyone else with a STACK or AIM digital dash has experienced when deleting the factory cluster. Or even people who just ditch the cluster and use like Defi or greddy gauges.

[dbeiler]

Originally Posted by brndck

so to take this conversation in a slightly different, but hopefully useful direction, when I ditched my stock cluster for a STACK cluster, my alternator would not charge upon starting up the vehicle. BUT, once I rev the engine to about 3-4k, it would kick on and begin charging. The stack cluster doesn't use any of the factory wiring, so the connectors for the factory cluster are just unplugged and left hanging.

long story short, the exciter from the cluster is NOT the only way to trigger the alternator. (I've had this stack cluster on 3 s13s now, same result on all 3 cars)

Nissan explained how this works in a TSB. Here's a quote from another alt thread I replied to:

Originally Posted by dbeiler

Here is a paragraph from Nissan TSB NTB94-011 (page 4) to prove my point:

Charging System Operation When the ignition switch is in ON or START, current from the battery flows from the L terminal to the E terminal of the alternator, causing the CHARGE lamp to light up. Then when the engine is started, the voltage output increases as the alternator rpm increases. When the voltage output becomes greater than the battery voltage, current for recharging flows from the B terminal. Simultaneously, voltage at the L terminal disappears, causing the CHARGE lamp to go out. Note: It is possible for the alternator to charge, with the "L" circuit in operation by accelerating the engine so the RPMs are above 3,600. The current will raise high enough to complete the field current. The alternator will continue to charge until the engine is turned off. Alternator will not charge below 3,600 RPM because the field current has not been turned on by current induced by residual magnetism. Checking Terminal Voltage When diagnosing the charging circuit the same precautions and test methods as used for the starting circuit should be followed. Visually checking for wires and connections that are loose, corroded, chaffed, etc. can aid in the diagnosis process. The voltage drop method can also be used to isolate poor connections and unwanted resistance just as in the starting circuit.