2000 V70R electrical issue continues

[scot850]

Some may recall I posted a thread about 6 months ago about an electrical issue which I though might be headlight switch related.

viewtopic.php?f=1&t=95893&p=561478&hili ... ry#p561478

This came about when I had a mishap trying to re-fit the battery at -20C and a gimpy arm. Managed to somehow get the +ve and -ve battery cables to both touch the terminals at the same time causing a large fat spark. When I tried to start the car I got all sorts of weird dash issues when I tried to switch the headlights on.

Thinking I had maybe damaged the battery I took it back to the supplier under warranty but when they tested it they said it was ok.

I re-fitted the battery to run the car around to our new garage and this time all was well. No issues.

Car has now been standing for about 5-6 months with battery out and I have charged it with a trickle charger from time to time.

I made sure it was charged about a week ago, and due to a delay fitting the battery decided to make sure it was fully charged. I was surprised to find that on a 2A charge for about 14 hrs it was not up to full charge so ran it at 4A for another 2 hours before fitting it, but it was not showing full charge even then.

I fitted it to the car and tried to see if it would start. It did with no problems but again the issue with dull dash lights and the turn signal indicator arrows glowing for both directions.

I planned to move the car into the new garage from the old one to work on it today, so put it on trickle charge again over night while still connected to the car. After another 12 hours it still was not charged fully so ran it at 4A again for a few hours and this time it charged fully.

Went to move the car and again started no problem and ran fine but again the dash light issue.

I removed the battery and checked the static voltage and it showed 12.6V. Weird thing was I checked it again a few hours later and it showed 12.8V??

I checked the 3 accessible grounds (the lead at the back of the motor to the firewall, the battery main lead to behind the LHS front headlight and there is one on the inner LH fender tower behing the airbox. All were fairly clean but have rechecked for continuity after cleaning and re-fitting and all are good.

I know there are more grounds in the engine bay but have not gotten there yet.

I have tested for current draw on the battery. My car has always had a fairly high draw (around 60mA) due to the immobilizer unit fitted. However the immediate showing was 140mA and it drops down over maybe 15 seconds to a fairly steady 100mA. So I am thinking something got damaged in my initial short issue last winter. I will now do a fuse pulling process to see if I can throw up the offending circuit and hopefully what is causing the draw.

Any other things I should be checking??

Thanks,

Neil.

[Clemens]

What a nightmare, Neil! I feel with you.

I guess pulling the fuses is the right way, but still I wonder how such a minimaö draw of 140 or 100 mA could cause a fair amount of trouble. Just the low beams on would cause way more power drain. But I had weird things happen to my dash lights with a badly charged battery as well.

A friend tried to jumpstart my VW T4 Van and hooked up the jumper wires the wrong way (+ to -), but surprisingly nothing happened except for a big spark.
I hope you get away lucky.

[volvolugnut]

This is not an answer from any experience with Volvos, but from electronics in general. Get the detailed electrical schematic and start looking for any diodes in the dash and turn signal wiring. The reverse power may have popped a diode somewhere. If electronics are not your thing, think of a diode as a one way valve for electrical flow.
volvolugnut

[scot850]

Thanks for the encouragement guys. It will be one of my 'favorite' tasks playing with 'electrickery' stuff!

It is usually a laborious task with no guarantee of success or obvious issues.

I just wanted to clarify, the battery was never connected incorrectly! What happened was as I was fitting the battery into place, the +ve and -ve terminals managed to slip inward from where I had them and they managed to touch their respective terminals only.

There was a large spark which is what worried me most. Even now, when I connect the -ve battery terminal there is a bigger spark than I normally get which says to me something may be shorted allowing it to be 'live', hence the larger spark.

Oh well, I'll let you know how it goes!

Neil.

[scot850]

Well I am hoping I got lucky (if you call this lucky!). I decided to go with gut feeling (as I have a lot of gut! Ahem....!) and swap out the main headlight switch. I used the reasoning that the issue started with switching the lights on after the 'incident'. As I have several spare used switches it was worth the 2 minutes it takes to swap the switch. Sure enough once I tested the current draw again it dropped from 100-120mA to 75mA and then dropped down to 45mA and sat there steady. I'd call that a result! I won't know for sure until I drive the car more and see that all stays good on that front.

Only thing was that a certain idiot (name held for privacy reasons......... ) left the driver's door open when trying to test the current draw after swapping the headlight switch and promptly fried my little multimeter. Fortunately this is not the first time I have done this so I knew about the fuse inside it and had spares. Now only if I knew where I had those stored since we moved???

(Result found them! All is good).

Neil.

[scot850]

Well in spite of my (large) gut feeling, clearly the headlight switch is not the route cause of the issue. Tonight my wife used the car and the problem has reoccured as soon as she used the light switch. So clearly there is a bigger issue at large here.

Did I ever say I really, really hate this car!

Neil.

[abscate]

A spark when connecting the battery on a 1999- is normal. a 100 mA draw is a big spark, blue and white.

No damage from that.

45 mA static draw after rest is ok too


Inspect wiring loom for damage from Norway rats who have emigrated to Canada, we put ours to work doing Door Dash deliveries …

[scot850]

Thanks Abscate.

The car has been running fine but only driven during the day, and other than the check light for the evap leak, the car has not thrown any codes since the original issue surfaced. Last night was the first time the car has been driven at night, and therefore the headlights were switched on. Issue then happened again. Wife managed to get the car home, but no lights, dashlights or speedo and a load of warning lights.

Before reaching for the matches decided to go check if codes still there with lights turned off. Lots of warning lights, all the lesser warning lights seem dull compared to SRS, Engine Check, ETS and trans.

Started car and all lights went out except ETS, Engine Check and flashing Trans arrow.

Switched off. Removed headlight relay and started up again. All lights went off except Engine Check. Pulled code with my general code tester set to Volvo. All that came up was a P1633 Speed signal missing. Reset that and re-started and car running ok with headlight relay out. Still does not confirm the relay is the issue. Tried to open the headlight relay to see if anything burnt but those suckers of small tabs refused to let me remove the cap. Didn't want to damage it.

Decided to do some more reading on MVS. Saw a post on lighting and warning errors and saw one talking about Power Relays possibly being the issue (#105 and 106). 106 was the problem one for the individual. He swapped 105 and 106 over and all worked as it should. So went to try doing the same, but the 2000 fuse box does not have those 2 relays at all, just empty spaces. I'll upload pictures later when I can download the pictures onto my desktop.

I also tried swapping the keys over to see if I had the same issue as abscate on the key barrel.

Swapping the keys made no difference. I need to check back but I think the electrical portion was swapped out a few years ago, but think I may have another new one somewhere.

What is confusing me is how can the issue affect so many systems and has anyone got any ideas what can affect all these things?
I would have thought the ignition switch (mechanical) is unlikely to be the issue, electrical possibly.

I have left the headlight relay out. Are these still available new? Can't seem to find them on Volvo parts websites.

I am looking at the Haynes manual wiring diagrams but they seem to be more focused on the -98 years.

Thanks,

Neil.

[scot850]

I have attached the pictures of the main fuse box for my car below. This looks different to all the ones I can find and there is no info I can find other than the self explanatory Light Relay as to what the rest are. Any one able to 'enlighten' me?

Main Fuse box

Headlight relay

Appreciate any help/guidance.

I have found a new electrical portion of the ignition switch but don't have a spare light relay. Looks like PnP may be on the cards tomorrow!

What I am trying to find if this car has the 'Power' relays and if so are those the smaller gray ones on the lower LHS of the relay section? Headlight relay is removed and fits in the blue/yellow plug ins on the RHS.

Neil.

[abscate]

In Canada you guys have mandatory Daytime Running lights or DRL. WE can toggle ours on or off in the States with a little switch on our light switches you turn with a small screwdriver, your switch won’t have that unless someone has replaced it with a liberated one from South Canada.

Thst mightbe worth checking. The wiring would be different.

103 is your fuel pump relay. They got better on the 1999 amd 2000 models so we don’t have to carry them around like the rest of the plonker P80s

The grey ones are X load reduction relays for various things that use high current, but are turned off when you crank the car ( headlights, wipers, blowers, heated third seats , etc)

Next time you read someone post how you can diagnose a bad battery by watching the headlights while cranking, you can admire the flow of worthless information on the internet from afar.