Dead SVXes

[LarryIII]

Thanks Nori,

I am a retired mechanical engineer. I have some (not a lot ) repair experience on SVXes.

I may not be able to work on the car tomorrow because rain is predicted and the car is outside. It is drizzling right now and of the outside cars are covered. Only the '94 SVX (Pearly)and the Viper ( Vinnie) are in the garage.
All our cars have names.

[Noriyasu]

Hi,

Getting wet in the rain and catching a cold is foolish. Do it on a sunny day.

Me and my wife have a total of 5 cars. This is rare case in Japan. Most Japanese family can only have one or two cars. Also many people in big cities do not own cars.

I like cars, so I moved to the countryside. There are many villas around here, and many classic cars are stored.

I build additional garage, but I can only put 3 cars in it totally. Two are outside.

In Japan, the tax does not decrease even after 25 years have passed since the car was manufactured. On the contrary, it will be increased after 14 years and 18 years.

In Japan, it is not easy for ordinary people to own a classic car that does not work. I think SVXes in Japan has decreased considerably in the last few years. People are forced to let go when repairs become difficult.

I hope as many SVXs as possible survive.

[LarryIII]

Both '92 SVXes are dead. I am quite perplexed. Their batteries are nearly brand new and fully charged. The fuses in both cars are good and the grounds seem to be good. When I open the doors, the dome lights do not go on. When you put the key in the ignition I do not hear the fuel pump like I used to or see the gauges wiggle. When I turn the key to start, nothing happens. Nothing makes sense.
What is the black plastic electronic cube located under the dropping resistor and what is it's function.
My '94 & '97 SVX does not have this cube. Maybe this cube is the reason the cars are dead.

[oab_au]

I don't know that that could be, my 95 doesn't have anything there, and have never seen one, maybe Noriyasu has seen one and knows that it does.

[Noriyasu]

Hi,

If not just the fuel pump but all the lights don't come on then it could be an electrical issue. It may not be that serious.

First, I attached a photo around battery and resistor of my SVX. I can not find any black plastic electronic box there. If you're talking about the unit under the main fuse box, it's the cruise control actuator. I don't think you need to think about cruise control for now.

Have you checked the box fuses called SBFs as well as the blade fuses?
They are four red ones and two green ones in the picture.

for example, if the room lamp (I think you call it the dome lamp) doesn't come on when you open the door, it it related to the No.15 blade fuse in the sub fuse box under the A-pillar (under the driver's seat side) and SBF5 in the main fuse box.

The interior lamps are controlled by a delay unit for delay in turning off. It's a little complicated.

To make matters simpler, check your trunk lighting. It comes on by opening the trunk without turning the key as long as the battery has power.
Only the battery and FL1.5 and SBF3 and the blade fuse FB25 (10A) are related to the lighting in the trunk.

No ECU is involved in trunk lighting. So, if the trunk lights come on, some battery power line is available.

Maybe the black box you found is an immobilizer added by someone? Did you buy the `92SVX new? Didn't you add an optional immobilizer?
If you remember having the immobilizer on, I recommend bypassing it.

wish you could take a picture of it and upload it.

[oab_au]

As there is no sign of any electrical activity, it looks like no charge from the battery. but you say they are charged.

Larry can you check it with a test light across the terminals, to see?

[LarryIII]

I did that already. They are fully charged. I am assuming both cars have the same problem, since their symptoms are identical . That may be not true and faulty reasoning on my part. It's got me stumped Thank God Pearly and Subydoo are working fine.

[Noriyasu]

I think you need to confirm the battery voltage again. pls measure it with circuit tester.

Have you not start engine of the '92SVX for more than a few months? If so, the battery may not come back even if you recharge it. Once the battery is fully discharged, it cannot be recovered.

If you can't think of what caused your car to break down, I think that it seems battery problem. Two cars are unlikely to break down equally at the same time.

1) First, with the key off, it must be above 12V.If not, you need charge again.

2) Next, with the key ON it should be above 11V. If not, the battery may be dead. This car consumes more than 4A of current even if the engine is not started. Try replacing it with another live car battery. If the battery is the reason, it should work.

3) If voltage is almost same as 1) when you turn on key (not start). Power may not be supplied due to fuse, immobilizer or wiring disconnection. The battery voltage should be down when there are some load. If there is no change, the cause is probably not connected somewhere.

[LarryIII]

I just tested the batteries with my VOM. Now I know "Bad Batteries".
Both batteries were bought together new and installed about 14 months ago. Both cars were started and driven last Oct. and both have been on a trickle charger over the winter. SVXY's battery showed 1.5 VDC on my VOM and ALCYONE's showed 3.0 VDC. I thought the batteries were good because my electronic battery charger told me that both were fully charged. I will dig out the receipt for both, return them and get new ones. I always keep battery receipts in the glove box.
Another problem solved. Thanks for all your help guys.

[LarryIII]

I now have the battery receipt in my grubby little paws. These batteries were bought on 6/15/2022, so they are less than a year old. They were bought at the same time from my local NAPA store and cost $200- each. They will be returned for new ones tomorrow morning because I do the weekly shopping for the house on Saturday mornings and the NAPA auto store is right there. Looking at their serial nos., they were most likely made in the same batch.
Thanks for all your help.

[Blacky]

A battery can show full voltage and still not start the car. You need to do a load test to know the real condition of a battery. It may have voltage but not the cranking amps necessary to start.
Faulty new batteries are becoming more and more common.

[Noriyasu]

Hi,

It seems that there was a problem with the battery.

Battery may not be reliable enough. SVXs tend to consume more electricity than cars of the same age, putting a strain on batteries and generators.
I prefer Bosch or GS Yuasa batteries with calcium alloys, even though they are expensive. I live at a high altitude and it is very cold in winter. I don't drive the SVX in the garage during the snow season from December to April. Just to be sure, I charge it with a charger about once before spring, but there is no problem for more than 5 years.

Bosch's Hightec Premium batteries were previously made in Japan. Made in Korea now. But the reliability is pretty good. GS Yuasa is made in Japan, but quite expensive.

I don't know much about the high reliability batteries sold in your country, but batteries are a very important part of a gasoline car, so I recommend using a good one. A good battery will help with better ignition, more torque, and the engine will run smoother to higher revs.

Thanks.

[LarryIII]

I brought back the batteries to the store where I purchased them. They tested them with their own tester and were surprised to find the same thing I did. They gave me 2 new batteries for free.

[Blacky]

Excellent! So...both cars now start perfectly?

[LarryIII]

I will install the batteries tomorrow morning. This holiday weekend is friends & family time. I have to get my priorities straight or I'll never hear the end of it.