Pulsing Lights.

[Aerosteve]

All the lights, including the panel display and headlights on my 1998 XJ8 are 'pulsing' ie dimming and getting brighter at about once per second frequency. This is evident at tickover and during normal driving. The voltage at the battery is also pulsing at that rate between 13 and 13.4 volts. I can hear some pulsing also from the area of the front of the engine. Is it an alternator issue? Anyone experienced this?

[MTDJAG]

Hi, I have exactly the same issue....did you ever get any response on this or got to know the fault?

[ptjs1]

This problem seems to crop up now and again. The most common causes seem to be:

- Alternator rectifier. Most common and most expensive
- Bad earth connections, particularly main battery earth
- Poor connection on alternator connections / multiplug

If you've got pulsing volatage reading on battery, I would suspect alternator rectifier.

Good luck

Paul

[Brakebuster]

i agree


and it would almost be cheaper to buy a complete used alternator to swap out rather than getting the rectifier for it,

the rectifier is bolted to the alternator converting AC voltage to DC for the car to use

BB


ps, the regulator/rectifier is available from Jaguar Heritage for £111 plus Vat

[Brakebuster]

just as a side note


make sure the alternator belt is fitted correctly and not making the alternator struggle under load

a simple check is twist the belt, it should only twist a maximum of half way , any more means its loose

BB

[MTDJAG]

Hi guys, tx for all your suggestions. Turned out to be the alternator. New fitted and all OK. Heard from a service tech that I was actually quite lucky as the fluctuating voltage can hit some of the electronics and the complete PCB's out.