Hi guys, any idea why sometimes during driving the abs light comes on and the rpm tach stops, than after a minute or two the abs light goes off and the rpm tach starts working again.
I am guessing is a connector somewhere.

Ideas where to look are apreciated.
Thank you

Oh and one more question , the compressor cycles on and off during normal operation, So if the system was not filled to the proper pressure level than the compressor would run continuously or it will still work normally? And what side effects would be running the AC with low pressure.

Thank you

Check the OVP relay

I checked the OVP relay and it looks like somebody before me change it.

With the car running, put your hand on the relay and move it a little. See if that changes the symptoms. Mine would work if I did that, only to fail a few minutes later. $95 at the dealer for the relay.

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I cleaned the socket for the OVP with contact cleaner and I will drive it and see if the problem comes again. Until now it's working

thank you

While the car is running, and showing the ABS light, check the voltage drop between battery positive and the red & yellow wire on the ABS pump unit.

If the OVP is working correctly, there should be a very small voltage drop, say 0.5 volts.

If you find a large voltage drop, give the OVP a wiggle, and see if the voltmeter jumps around a bit.

I suggest this, as it's much easier to back-probe the ABS pump connector than it is to get a hand to to and to disconnect the OVP (at least this is true for RHD vehicles in the UK)

Hi

After reading some of the posts I took the OVP out, open the casing and re-soldered all the contacts inside. A 10 minute job. After doing this the abs light never came on and the rpm tach is working continuously. Also before fixing the OVP I noticed that when I turned the headlights on with the engine running the yellow warning light from the dash near the abs light would turn on , indicating a lighting system short circuit, but after I fixed the OVP this problem was solved also.

Thank you everybody for the replies.

>>but after I fixed the OVP this problem was solved also.

Thanks for reporting back about your success in fixing the fault.