2002 s60 Electrical Nightmare!

james166 · Post by **james166** » 09 Apr 2015, 16:20

I have a Volvo s60, non-turbo with about 95k on it. About 2 months ago, I got the Service Airbag... error, went to the dealer, had it reset, all good. Then 2 weeks later, my battery died (it was old anyway). Got it jump-started, went to Sears, got their best battery. Voltage measures about 12.2V not running and 14.4 V when running. Another two weeks later, my instrument cluster (DIM) fails. Also had all sorts of accessories acting weird, such as lights staying on inside the car, climate control turning on and off at random. Rushed to the local Volvo expert, and was told I needed a cluster rebuild. A few days and $700 later its back up and running. A few days after that, SRS message comes back and the cluster fails again (actually is intermittent). Go back to shop, they take it to a dealer who says the passenger's side door lock module is bad (apparently any module in the car that is faulty can cause a cluster fail). OK, replaced the module, reprogram car and I'm good to go. But not far. A few days later it does the same thing. Go back to shop, car goes back to dealer, where they reprogram the electronics, and do the diagnostic test which shows everything good. Works for a few days, same thing happens again. Removed the cluster myself and called the company that repaired it, since it has a lifetime warranty. The company says the cluster can't be the problem since they fixed it, it must be the CEM. So, I removed the CEM and sent it to a company that replaces them and clones your existing unit. Got it back (noted they found an fault in it related to the passenger side seat heater) and re-installed it. I should mention that throughout all of this, the engine and transmission have run fine; no problems starting, shifting or running. By now I've spent about $1500 on this problem.
Cluster seems OK now (but tomorrow's another day), but certain problems I've had all along concern me. First the driver's side door lock button works sometimes but not always. Could be just a worn button? More concerning is that after I turn off the car, about one minute later (not the 45 minute after blow thing) the blower motor comes on, stays on for about a minute or 2, and then turns off. Never had that happen before all this. Of course, I still have the SRS service needed message.
Any suggestions about what to do next, short of finding a very high cliff?

Post by **oragex** » 10 Apr 2015, 04:24

I would check the alternator or it's regulator, but wait until others here post their suggestions. The alternator is the one charging the battery, and when the battery is not properly charged, the network which link all these electrical components that you had acting up, gets confused.

Careful if replacing the alternator (or it's regulator), it's regulator has a part number that's confusing and it must match for it to work properly.

The CEM is also a sensible part, but I don't remember which model years.

If the car is fine now, only thing you need is a drive back to Volvo to have them reset the SRS message - this message pops up when disconnecting anything dash related electrical, such as the DIM, without disconnecting the battery first.

I think the blower running it's related to it drying the A/C evaporator, so it doesn't moist - perhaps Volvo added the setting while having the car.

draser · Post by **draser** » 10 Apr 2015, 05:53

My first thought was alternator as well, but then I saw that it outputs 14.4 volts so diodes, regulator, cables and clamps are good. There's an alternate component that needs be below a level for electronics to work well, so you can put a voltmeter on it's lowest scale across battery and measure that. Did you measure 14.4 across batt posts, correct? Because if you measure on the cables and have dirty clamps batt will see a lower voltage. Also, batt acts as a filtering capacitor to smooth out the alternate component from alternator and if posts or clamps are oxydized, corroded then it can't do it's job. The other question is, in removing all these modules did you notice corrosion at connectors, moisture, etc?

Post by **precopster** » 10 Apr 2015, 06:05

When they replaced CEM some of the programming didn't come over in the clone. The after blow characteristics are a programmable item using cloned Vida/Dice. The door lock thing is normal for a 15 yo car.

You need to reset the SRS with Vida/Dice or Volvo compatible scanner. No big deal as you probably forgot to disconnect the battery while you were fiddling with all the modules.

By the way the symptoms you describe point directly to the CEM. I'm surprised that they didn't blame the CEM in the first place.

Post by **vtl** » 10 Apr 2015, 06:37

Yes, afterblow is normal.

Car has two separate CAN-bus networks: high-speed for critical components, like engine, brakes, transmission, and low-speed bus for everything else. Something went south on the low-speed bus.

Cluster repair is not a throw-away money, 2002 still has tin pest problem, it is only a matter of time and bad luck when it fails. Cluster in my 2005 XC70 failed last fall, I had to reflow soldering and add a few fins, so the problem was there even 3 years later.

What I would do is attaching Chinese ten-bucks copy of Saleae Logic analyzer to low-speed CAN-bus at AUM socket (green socket attaching to the back of HU-6xx), recording transmissions and looking at those with bad checksum. Then google which computer has this CAN id for this model year. If corruption seems to be in random modules and you can't determine which one fails to send correct message more often than others then you need to do triage and disconnect modules from CAN-bus one by one until the problem goes away. That would be your bad module.

The reason of why standard OBD-II port can't be used is it's not attached directly to network and the traffic is only replicated if special activation is sent to CEM. The AUM port (or any other internal entry point) does not have such restriction.

james166 · Post by **james166** » 10 Apr 2015, 07:44

Thanks for the replies, it's great to have some ideas on this. One thing I forgot to mention is that the car has an aftermarket remote start. I'm going to attempt to disconnect it and see if it affects my heater blower problem. Barring that, I'll have to look at various suspect modules. My question is, if I disconnect a module (such as the climate control or power seat), will the car still run? Or will it get totally confused, implode and disappear into a black hole?

Post by **GBS** » 10 Apr 2015, 08:19

We had similar issues with the SRS airbag coming on in our 02 V70 and it went back to dealer, they reset it and gave it back but on the way home it came back on, after having it for a couple of days, and $400 later, they said it was a relay that failed. It was a while ago and before I started working on the car so I didn't pay attention to what relay but I think it was for either the climate control or SRS itself. We did not have issues with the DIM though but thought it worth mentioning.

02 S60 non-turbo with 96k on it, great car! Do not look for a cliff, that car has MANY more miles in it.

Post by **vtl** » 10 Apr 2015, 08:22

You will need to reset SRS error if climate control is removed. Can be true for other modules.

Post by **GBS** » 10 Apr 2015, 08:31

Oh and I've had that intermittent lock problem, I replaced the "door latch actuator" on passenger side and problem solved. Mine sometimes got into a deadlock situation where the car sensed the wrong position for the lock and started doing odd things unlocking and locking.

I saw a lot of codes about the door not being locked, maybe they can check it when you reset the SRS. $150ish cost, nice clean dry area to work in but a bit tight to get part in and out. Easy DIY, I always assumer 02 Volvo owners are either DIY or soon will be

bigbrain · Post by **bigbrain** » 10 Apr 2015, 12:19

Sadly all typical volvo problems....on the up side they do keep going regardless! I had similar gremlins....airbag turned out to be a worn wire under the drivers seat...I'm 6'2 and my wife is 5'3 so the seat goes back and forth a lot...kept resetting and kept coming back when I got in the car! Door lock problem has now gone...the things I changed were...indicator stalk...door lock repaired....door seal replaced. I think the last item caused a lot of my problems as water was getting in and under the carpets without me knowing about it.....took 2 weeks to dry out but issues are now gone....oddly the remote stopped working during all of this...now fixed. As I said it's a volvo....now the power steering is not working properly!