2005 V70NAM56 servicing Pump Electronic Module 30769225

Post by **abscate** » 20 Jan 2018, 14:15

Block, jack, and support Car

P2s have the pump control module either on the fuel tank or in the spare tire well

This procedure covers the PEM on the steel tank

On the passenger side, the PEM slides into a mount on top of tank, and is secured by a 7mm hex bolt. Once you loosen this bolt, a metal bracket releases and the PEM slides out. One electrical connector to release on top.

It’s hard to see what is going on, I used a flashlight and an inspection mirror to get my hands around this one.

Look at all that crap from the heat sink oxidising. Some of it certainly landed on the circuit board and caused failure intermittently

The PEM functioned after cleaning but I am replacing it

Post by **mrbrian200** » 21 Jan 2018, 01:06

If Bosch had merely applied a conformal coating to the boards in these most of them would probably last the life of the vehicle. They have to know that salt/moisture gets drawn in past those rubber gaskets with every heat cycle.

Post by **abscate** » 21 Jan 2018, 02:55

Bosch probably figured it would get mounted in a environment like the spare tire well...

I don't think this was intrusive but Al oxidation inside the PEM aided by water vapor intrusion, perhaps.

Post by **RickHaleParker** » 21 Jan 2018, 03:54

If Bosch had merely applied a conformal coating to the boards in these most of them would probably last the life of the vehicle.

Planned obsolescence. Were talking consumer products not industrial products.

START International PC101 is the conformal coating I prefer but, it is hard to find if your not a production manufacturer.

Post by **abscate** » 22 Jan 2018, 04:07

Opening the case

In the pictures above, opening the case is shown, there are two kinds of clips along the side of the PEM case , one which secures the case and the other which serves as a pry point to top the case open.

The corner clip is the securing one, the middle is the pry point.

Post by **abscate** » 10 Mar 2018, 05:40

Link To waveforms of

ECM to PEM. 25 kHz 12 volt

PEM to pump. 500 Hz 12 volt

Here

viewtopic.php?f=9&t=84648

Post by **mrbrian200** » 10 Mar 2018, 13:36

abscate wrote: ↑21 Jan 2018, 02:55 Bosch probably figured it would get mounted in a environment like the spare tire well...

Very Possible. But when Volvo decided to mount it 'outside' they could have easily changed the spec with Bosch to specify either a conformal coating or it be filled with potting gel. Potting tends to be the anti-corrosion weapon of choice for external modules on non mil-spec land vehicles. Somebody somewhere dropped the ball. Either that or Europeans have some hissy conniption against utilizing basic anti corrosion measures. Bosch certainly has the means to fill these with potting gel and I doubt it would add substantially to cost -- once they passes functional QA you just squirt the crap in and stick the cover on. Potting is an soft set epoxy resin that will cure in a sealed environment.

External modules on most all my previous domestic vehicles were usually filled with it.

If the issue with traditional potting resin is recyclability, then you spend a little on R&D to develop a new material that is environmentally friendly.

Post by **cn90** » 01 Oct 2020, 12:41

I agree with replacing it.
It is just electronic component(s) failure more than sand getting in.

When buying used on ebay, I'd recommend searching for a PEM unit with Velcro (check ebay photos) bc
Velcro is used for PEM units that are located inside the car (under rear seat or trunk).
These units are probably better than the units that sit outside (under the car).

Although the video by "Peppermint" is nice, there are some minor errors.
Peppermint said the bolt is 6-mm and commented on the metal plate orientation:

1. The bolt is 7-mm, not 6-mm.
The retaining metal plate should be oriented as in my photos below (the Volvo logo
facing you, good advertisement lol).

2. Do NOT disconnect the connector in situ, very difficult,
one can actually damage the connector doing so.

3. The trick is to loosen (NO need to remove) the 7-mm bolt,
slide the metal retaining plate out. Then slide the PEM out.

4. Now you can squeeze the tab with fingers (usually this is NOT enough to lift the
inner tab enough), so use a small screwdriver GENTLY to lift it up as shown.
Then it will be easy to disconnect.

Hope this helps...

: 2004-V70-PEM-01.jpg (297.01 KiB) Viewed 2869 times

Post by **cn90** » 06 Oct 2020, 15:52

So,

I was looking at a similar thread 2005 S60 No Fuel Pressure:
viewtopic.php?t=66777

I noticed a burned chip, particularly the PBYR 1645 B.
The chip next to it is BUK9606 55A.
Please see photo I took from that thread above.

These chips can be bought at Mouser or Arrow Electronics for $1.50-$2.00/each.

Has anyone here attempted this kind of repair, basically un-solder and re-solder the new chips in for a couple of dollars?
I am now thinking the PEM mode of failure has little to do with exterior vs interior mounting (although exterior mounting can expose the sand/salt etc.)...
I am thinking component fatigue and failure with time/hours of operation.

Just curious...

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