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Discussion Starter · #1 ·
My V70R has been an absolute nightmare to own... it has driven me insane and caused me WAY more stress than a car should. And for what? I'm not sure I even want this car anymore. I've been trying to figure out a set of codes for a while now, and with more and more weird issues appearing, I'm really thinking the ECU is at fault.

The codes are ECM-6B00 MIL signal too low, ECM-6300 ETS warning light signal too low, and CDM 000D (which doesn't show up as much, but it has a knack for reappearing every now and then) communication, ECM internal fault. I have taken all steps to diagnose these problems, and I cannot find anything wrong in wiring, connectors, or the cluster (which I just tested today with a replacement unit). Same codes showed back up. When I check the wires related to these codes, I see about 25 ohms to ground when the cluster is plugged in. When I disconnect the connector on the cluster, they both go infinite resistance to ground. I checked the wiring along the passenger fender (where these wires should run) and all of the wires look to be in good shape and in tact. I checked the resistance in the wires from end to end, cluster to ECU, and there is not excessive resistance.

With all of this in mind, the only logical explanation I can come up with is that the ECU is the problem.

I've also been trying to figure out a low/erratic boost issue, the ECU is commanding boost, yet for some reason the car isn't able to build it. I think I might hear a boost leak, but I can't find one after smoke testing and pressure testing. I've taken all steps necessary to try to diagnose that problem as well, but currently I'd like to figure out this issue first. With any luck, maybe the ECU isn't giving the correct signal to the TCV as it thinks it is and that's why the boost is acting so strange.

Back to the electronic related issues... lately my tach has been dropping to 0 while driving. No other problems, but it just randomly drops to 0. Sometimes it comes back within a few minutes, other times it doesn't.
Even more recently, if I turn the car off when the tach isn't working, the CEL pops on and eventually the ETS light. It'll rev itself up a few times, and eventually settle at a high idle, I estimate around 1,250 RPM (I'd know for sure if the tach worked). Then, it gets all misfire-y, like the ETM is bad. I know the ETM is fine, I've replaced it 4 times now and this one is a 2006 production date, yellow sticker. Tested fine on the VIDA ETM test. I suppose the MAF could be a problem too, but that doesn't explain the ETS and MIL signal too low and "ECM internal fault" issues.
Anyway, it most recently did this today. I managed to get it home from the store, but it wasn't in its usual limp home mode when there is a problem like this. This is the second time this has happened now without going into a limp home mode. Still made full power (which is relative with this car on its lame 10 PSI).
When I got home, I pulled the negative cable and replaced it, and the car started up and ran just fine. I pulled it back into the driveway, hooked up VIDA, and no new codes to report. Last time I was able to pull a vehicle speed sensor code (NOT ABS wheel speed sensor, some other speed sensor I was not aware of) and a fuel level sender code and some other codes. All related to sensor communication, which is what led me to replacing the cluster. From what I've seen, that's simply not the cause.

I'll also mention that it took several tries to get it started after I read the codes. This only happens when CDM-000D appears.

The car has a Hilton stage 1 tune, and I've tried diagnosing this problem on the stock tune as well with the same results. It's not the tune. I'll drop test the cable between the battery and alternator, but the main fuse box cable does not have a significant drop (can't remember the exact number, but it was not enough to worry about it, maybe 0.1V).


Sorry about the long winded post, but I wanted to make sure I got out as much info as I could. Anyway, is there an affordable way to get a replacement ECU? Also, what is the interchangeability between ECUs? Can I use any turbo ME7 ECU for 2000 models? I know some people can clone them, but I don't want to spend any more money on this car. Anything more than $200 I'd rather take the parts I want off of it and push it over a cliff. I've spent enough money on this car I'll never see again... worst part is that I have yet to drive the car on the full 16 PSI it's supposed to be making. I've owned it for over a year and I have not been able to enjoy it for a second. It's been a nightmare since day 1. Never meet your heroes, kids.
 

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Step 1: Check all your grounds. Random unexplainable intermittent electronics issues can frequently be traced to bad grounds.

As far as bad ECU or not goes....maybe ask Hilton if he has an ECU to try swapping. Tuners frequently have some around. He'd also be the one to know what ECU's he can flash for you and such. Heck you might be able to pick one up at a local pull-a-part lot for $30 and flash it. Just ask the expert
 

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Discussion Starter · #3 ·
I want to try to figure out the interchange on ECUs. I'm not sure if there is any technical difference between a GLT, T5, or R ecu. I want to figure out if it's as simple as finding one and loading the stock tune file or stage 1 tune file from the Hilton tuning suite program. I'll have to ask Rob about that one and link him to this thread.

I've checked all the grounds though, everything looks and tests good.
 

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Ecu are not the same across the cars you listed.


Sent from my iPhone using Tapatalk
 

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Discussion Starter · #5 ·
Ecu are not the same across the cars you listed.


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Didn't think so, that's why I wanted to make sure. Hopefully I'll be able to track down the right ECU if that turns out to be the problem.
 

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Low voltage issues? Just for grins, maybe pick up a
cheap cig lighter socket voltmeter and keep an eye
on it when you have problems. Could tell you a lot.
 

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Discussion Starter · #7 ·
I'll have to keep an eye on that, I'm not ruling out voltage as a possibility yet.

I checked over all the grounds today, everything seems to be good. I also checked power to ECU, the values on the two power supply wires are within spec according to the info in VIDA. Is a 0.08V drop from B+ to ECM B11 acceptable? Checking the voltage on this terminal with the key off, there is NO drop.
 

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Discussion Starter · #8 ·
I'll go ahead and add in the codes that appeared last time. I'm going to try to replicate the problem today and see if it throws these codes again.

It showed ECM-5000 A/C pressure sensor signal missing (likely due to no refrigerant in system... I'll worry about that once the car runs properly) and ECM-9300 clutch pedal sensor faulty signal (I have it plugged in but not mounted to the pedal... I can't mount it until I have an X70 master cylinder, currently running and 850 master). Also showed ECM-6120 cooling fan high speed signal missing (I had the fan speed signal wires reversed, that code hasn't appeared since I fixed that). Not worried about those three codes. Maybe the clutch sensor code, but I believe Andy said he's not running one and has no problem with it.

Now the codes that I feel are linked to the problem...
ECM-4050 fuel level sensor- signal missing
ECM-510F vehicle speed signal (VSS)- signal missing
ECM-6300 ETS warning lamp- signal too low
ECM-6B00 Malfunction indicator lamp (MIL)- signal too low

OBD2 generic codes are P1625 (same as ECM-6B00 I believe) and P1633 (same as ECM-510F?). 1625 has always been present, as have the 6300 and 6B00 codes in VIDA. Every time I clear them, they come right back. The latter show intermittent fault in VIDA, but they are always present.

I also checked voltage drop to alternator at idle, only 0.04-0.05 V. I don't think that's an issue.
 

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Pull out the ECU and check the complete harness...wire by wire
 

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Discussion Starter · #10 ·
I've already checked any suspect wire and I have found no issues. All the wires underneath the ECU are in good shape.
 

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Discussion Starter · #11 ·
Mmmmkay... so here's where I'm at...

I can confirm now that the buzzing/whining sound I've been hearing (didn't mention that in this thread, but it has been a problem) is indeed the ETM. This leads me to believe that the issue is within the ETM wiring. Which makes sense... the two lights that will come on and flash weirdly are the CEL and ETS lights, both of which can be triggered by the ETM.
I know the ETM isn't the problem, as I'm on my 3rd or 4th ETM now (failed rebuild and two dead ones).

I'm going to check the ETM wiring and report back. Maybe this is also the boost problem... just maybe.
 

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Discussion Starter · #12 ·
Update numero dos... I may have found a problem...

I discovered the green and white wire (pin 6 on the ETM connector, ECU side) shows about 12.8 ohms to ground. Not supposed to be like that as far as I can tell. When I pull the fuse for it (11B/2) it goes open circuit.
When testing the terminal coming from the fuse box/power on 11B/2, that shows similar resistance to ground. It goes open circuit when I remove 11B/1 (main relay fuse, powers ECU and is connected to the ignition switch). The other terminal that goes to the ETM shows 10.5 on the 20k ohms setting (so 10.5K ohms?) (I'll double check this, not sure there is much significance here).

Now this is where it gets interesting. I checked ECM B38 and B11 (the power terminals). I really don't think they should not be grounded, and they are. Looks like I have 26k ohms when 11B/1 fuse is installed. If I turn the ignition switch to KP2/on, I get 103.7 ohms. If I have the driver door open, it shows 95.3 ohms. I found that strange, so I continued and tested B11.
This shows 2.7 ohms to ground! That's with the door open and key off. If I close the door it starts climbing quickly and eventually goes open circuit. I got 2.4 ohms with the ignition switch in position 2, and 11 ohms in KP2 with the door closed.

The results were similar when I tested with the passenger and rear doors. The resistance was always lower with the door opened. I moved it around, but it seems it's affected only by the position of the latch, not the door. When the door is latched, there is higher resistance to ground on B11 and B38.

What do the door latches have to do with this circuit? This seems very weird to me.

When I remove the 11B/1 fuse, both ECU terminals are open circuit to ground, as I believe they should be.

I'm going to unplug the ignition switch tomorrow and test again to rule that out, but I'm hoping somehow that's the problem. This is very weird, I've never seen a problem like this before.
 

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Discussion Starter · #13 · (Edited)
I think I may have found the problem. There is definitely a short to ground. I noticed it first on ECM B38 and B11, both power wires for the ECM, and worked back eventually to fuse 15 in the fuse box on the windshield cowl. I noticed it was only showing continuity to ground at this fuse when a door was opened, and I believe it has something to do with the sensor for the interior lights.

What I found out after tearing a bunch of stuff down and disconnecting the three large connectors under the dash and the ignition switch ring (with the I, II, II markings, not sure what to call this) is that the wires are showing continuity to fuse 15, but also about 6.8 ohms to ground. I'm assuming that one or more of these three wires are damaged and shorting to ground between the fuse box and the other ends.

Hopefully I've isolated the issue and I can find exactly where the problem is tomorrow. I'll keep this thread updated. Feel free to add any info if I'm off track here and there's supposed to be ground on all these fuses... but I feel that shouldn't be the case.

Just copied this from my VS post, disregard the repeated information in the first paragraph!
 
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