V70 1997 Bypass Relay or not?

[revolvo]

I want to fit a Witter or PCT flange type towbar to my 1997 V70.

I have spoken to three suppliers; one says I need a bypass relay,
another says the 97-00 doesn't need one and the third said
I could fit one if I wanted but it was not necessary.

Can anybody give me a definitive answer please? Thanks.

[gpl1968]

If your car has a bulb failure warning system, then you will need a bypass relay of some type.
I just had to replace the towbar electrics on my 945 and bought a 7 way bypass relay made by Towing Electrics Ltd. (TEB7AS).
It was easy to fit as the Volvo's boot already has the necessary wiring tails.
It also incorporates the required warning buzzer(for turn indicators) and a trailer bulb-failure device (if bulbs fail, buzzer doesn't sound).
I bought one on Ebay for less than £20.
Whether your car needs all the features of the relay, at that price it seems silly not to use one and make life hard for yourself.

[revolvo]

Thanks - inexpensive to buy and easy to fit ...... eBay here I come!

[SteveSarre]

Hello,

I have a 1999 V70 and have fitted a secondhand Witter towbar, and have bought new electric cable and 7 pin socket and a TEB7AS bypass relay.

I have lifted the floor panel at the left rear so have fed the towbar electric cable up into the boot through the grommeted hole.

I have removed the carpet piece which covers the left side light cluster and can see some wiring.

But where do I make the connections? (Hopefully somewhere on the left side rather than having to run anything over to the right).

Thanks
Steve

[SteveSarre]

PS

If I lift up the plastic trim piece that goes from side to side at the rear of the boot, at the left, near the well where the towbar cable comes up, I can see a light grey plastic box which is called
Lamp control
with various part numbers
5KG 005 311-07
9442303
PA6-GF30

Googling for 9442303 I think it must the bulb failure module.

Is that relevant? (ie do I connect somewhere near it)?

Thanks
Steve

[gpl1968]

You might need to remove the side panel, under the window.
Look for 1x 12way connector or 2x 6way connectors here:


This wiring diagram should apply to your car:


Use the 15l supply for the 12v feed to the relay.
On my 945 the connectors had already been cut off the cables so I just soldered the new connections and insulated with heat-shrink sleeving.

[SteveSarre]

Hi gpl1968

OK thanks, I'll have a look. I had tried to remove that side panel but couldnt see what held it in place.

Steve

[SteveSarre]

Hi gpl1968

I removed that panel and had a look but there were no connections there.

I am still struggling to see where to connect to.
Are 24/70A and 24/70B relays or connector blocks - and where are they?

I may try a post in the V70 section of the forum.

Thanks
Steve