Relay question

[1197sts]

I am working on a 2001 Outback LL Bean doing some electrical troubleshooting. There are several black relays in the relay fuse box in the engine bay, and more in the relay panel below the steering wheel below the main fuse panel. They are made by Mitsuba japan. I have found some labeled RC-5001, and some labeled RC-5008. Are these interchangeable? They look like they should be, but the p/n difference makes me wonder. I realize there are lots of different relays in other locations just talking about the black ones.

[1 Lucky Texan]

I wouldn't swap 08 with 01s.

 

Tell us what problem you are having.

[1197sts]

My son has a 2001 LL bean, it has been having intermittent electrical problems. In the beginning it only happened once in a while but its a lot worse now.

When driving several of the panel lights will light up, it started out occasionally a "flickering light" now is fully on, typically it would be Charge, abs, and maybe more. The last time he drove it it acted like it was not charging, and of course it will eventually run down the battery in that case. sometimes the headlights don't work. I don't know if its related, the daytime running lights have not worked on this car since we bought it.

What he has checked so far:

Security of battery cables, checked all grounds he could find. Checked all fuses in engine bay including the SBF's, had the alternator checked, etc. It has not blown any fuses. Has swapped relays headlight relays no change. 

I am going to suggest he complete wring out the power supply distribution to start with, checking for continuity and shorts to ground.

This is a little complicated, he is in the military and I am trying to talk him through this remotely, and electrical troubleshooting is new to him, so he's got a steep learning curve.

[1 Lucky Texan]

ABS is very sensitive to system voltage. Some (maybe not all) of the symptoms point to a charging issue and, knowing that the H6 has a special alternator, I can't help wondering if it is failing or, if aftermarket, could be the wrong style. I thik getting a voltmeter on the battery terminals or elswhere and checking/monitoring voltage is a good first step. A fully charged healthy battery will be around 12.6v, charging can range up to over 14.4v, maybe 0.2 - 0.3 more. But the ECU in that car can hold charging current back.

are there any aftermarket electronics in the car? CB radio, woofer amps....etc.?

[laegion]

You also may want to make sure it's the correct alternator by checking info against the OEM version. The H6 Alternator is higher amperage output than the H4 alternator and that could cause a problem, especially with all the accessories running, and definitely if there are aftermarket drains on the power like 1 Lucky Texan said.

[heartless]

agreed - the described symptoms definitely suggest charging system issues.

you say he had the alternator checked - but was it in the car, and tested under a load?
testing them out of the car is a waste of time & energy.

battery should also be checked out - a dead/bad battery can kill an alternator, and a bad alternator can kill a good battery.. both need to be in good order

Most chain auto parts stores can do a charging system check in the parking lot. this is best done after everything is fully warmed up, too... sometimes it can be a heat related problem.

as was noted, a good healthy, fully charged battery will test at 12.6v to 12.8v at rest. with engine running, it should be around 14.4v or so.. if not (either above or below), either alt or battery - or sometimes both - is suspect.

[1197sts]

Sorry for the delayed response. He has not had much time to work on it. He did check out the power distribution wiring and did not find anything. I recommended to him to get the alternator re checked, that is the next step and of course he needs to get his battery charged.

For you who may not be aware, the H6 uses the ECU to control the alternator, it will vary the charge to the battery. The connector at the alternator has 3 wires going to it not two like the H4. The alternator output voltage will not be a steady 14 to 14.5v in all conditions. I have seen some reports there is a way to disable the ECU control over the alternator, apparently there is a Subaru Service Bulletin for certain models of forester but I don't have a lot of confidence in that until I get more information.

 

 

[1197sts]

Also there are no big aftermarket mods to the car it does have an aftermarket stereo but no extra amplifiers, etc.

It is definitely a H6 alternator, I am not sure which vendor the Mitsubishi is apparently the good vendor.

[lmdew]

Where is your son?  Someone close may be able to help.

Many Bases also have Auto Hobby Shops.  Some better than others.

[1197sts]

Update, yesterday he finally got some time to work on the car, he jump started it and the voltage was way low and jumping around so he decided to try a rebuilt alternator. Today he installed it and it is working well so far. There are no warning lights on at the moment and the voltage seems normal. With the H6 alternator it is a little hard to tell whats going on, the ECU seems to adjust the charge voltage in a range from about 14.4vdc to about 12vdc based on what it senses load to be. I will feel a lot better about it after he has put some miles on it.

BTW he is based at Camp Pendleton, he just found out he has a buddy with access to the auto shop so that will make a lot easier if he has other stuff he needs to work on.