1998 s70 t5 Power issue

peacock · Post by **peacock** » 11 Dec 2009, 15:13

This issue is different from the one involving the amp

It never seems as though there is enough electricity to run everything.

When the heated mirrors get clicked on the lights [even headlights dim a bit]

When the blower motor goes on the dash lights and head lights dim

when the radio is loud and hits a hard bass note the lights do the same thing

i am wondering if there is a relay that is responsible for this or if its something a lot less simple.

Post by **IVIUSTANG** » 11 Dec 2009, 15:23

When the lights dim, does it only do it when you first turn on the accessory or does it stay dimmer? It is normal for the alternator to have to adjust to a higher power load momentarily, but it should brighten back up almost immediately. Try using a capacitor wired between your battery and amp, it will help your battery and alternator have a much smoother load with less pulsing.

- Jesse

Post by **BEJinFbk** » 11 Dec 2009, 16:02

Step 1: Battery test
Step 2: Alternator test
Then look into the cables. Just dirty clamps will cause problems.
The main battery (B+) cable on these cars is a known issue.
With 11 years behind it, it's probably corroding someplace.
Sometimes you can't even see it without cutting them open.
Call DW for a price. Then put an hour or so aside for the job...
Check the neg cable, too. It's just as important.

peacock · Post by **peacock** » 11 Dec 2009, 16:42

I will look into both of these, a combination of each will probably do wonders.

Where to do I find a capacitor to place in the car?

peacock · Post by **peacock** » 11 Dec 2009, 17:01

i forgot to answer as well that it does come back up slowly. never fully but enough. just annoying.

Post by **IVIUSTANG** » 11 Dec 2009, 17:08

I'm sorry I thought you had an aftermarket amplifier. The factory unit shouldn't need a cap, but it will only help. Capacitors can be bought at any car audio store though. Regarding your amp draw from your other post, wire in a solenoid that is activated in position 2 of the ignition switch and have it also wired into the amp. This will stop 100% of the draw when it is not on. Multiple solenoids are not that uncommon in my world and work well in my opinion. Wire a solenoid into say... the cable going to the back of your stereo that will turn off any power going to your amp in position 0. As far as how to wire up a solenoid or which one to get, someone else better qualified can answer that, but this WILL fix your "amp amp" draw

The main reason I have more than one solenoid hooked into my aftermarket mods is to allow multiple conditions to have to be met for the system to activate, for example: my methanol injection solenoid turns on when the boost switch solenoid detects 3 PSI boost, BUT... I have another solenoid that will disable the pump once the pressure is at 140 PSI, both of these solenoids must be active for the pump to get any power. This is my preferred and cheap bypass option for annoying electrical problems. My HHO system is activated by a solenoid that is tapped into the headlight bulb socket, basically piggyback a system that turns on and off at the desired times.

- Jesse

peacock · Post by **peacock** » 12 Dec 2009, 15:28

Hmm this will make a fun project for over winter break.

Post by **BEJinFbk** » 12 Dec 2009, 18:54

peacock wrote:I will look into both of these, a combination of each will probably do wonders.

Where to do I find a capacitor to place in the car?

Don't worry about adding a cap or a "solenoid" that you don't need.
Stay on the path to Stage 0. Fix the car. Don't confuse the issue by adding extra stuff.
Keep it simple. Get it back to running the way the factory designed it to.
Consider that Tens of Thousands of other Volvos run just fine without any extra parts.

Post by **jblackburn** » 12 Dec 2009, 19:01

I'm thinking the battery cable idea is a good start. Honestly, it still sounds like an old alternator, I had cars that did the same thing under load, and ended up replacing the alternator in them both. My Volvo still has the original one though, and nothing makes a difference turning on except when I turn the fan up fast in the morning (I think it has a sticky motor and a hard time getting started). But the radio, defroster, all power windows at the same time, etc. don't make a difference in idle or dim ANY lights when all activated at once.

Just some food for thought

peacock · Post by **peacock** » 13 Dec 2009, 10:08

jablackburn wrote:I'm thinking the battery cable idea is a good start. Honestly, it still sounds like an old alternator, I had cars that did the same thing under load, and ended up replacing the alternator in them both. My Volvo still has the original one though, and nothing makes a difference turning on except when I turn the fan up fast in the morning (I think it has a sticky motor and a hard time getting started). But the radio, defroster, all power windows at the same time, etc. don't make a difference in idle or dim ANY lights when all activated at once.

Just some food for thought

I just replaced the alternator a little over a year ago.