Just trying to isolate why my seat heaters give off only a low heat. I have one seat bottom out, checked continuity (about 2 ohms), checked voltages (yep, 12 volts at the connectors, switch works, relay (for leather) CYCLES. The relay cycles mostly off (clicks on for a second, then off for say 10 seconds). So, I jumpered the relay and found that the seat got nicely warm. Ambient temp was about 5 C. Got the same, mostly off cycling at lower temps as well.

So the problem seems to be with the relay. But before I pop for a new relay, is it possible to repair such a fault or is it possible that the fault lies not with the relay but with a load drop somewhere like a dirty contact giving high resistance, hence high voltage drop under current load?

Any wise words?

Bill
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Volvo Info Site 1990 745GLE 16valve

It is normal for the relay to cycle depending on the temperature.

Have you checked both sets of heaters in the seat? There are actually 3 heating elements. One in the seat which get 12V and a second one in the seat which is in series with the backrest pad. If any one of these elements is broken you will be missing half your heat.
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Paul NW Indiana '89 740 Turbo 108,000