Timing belt warning system
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Nordschleife Master
Joined: Apr 2003
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From: Abbotsford B.C.
Timing belt warning system
Hey does anyone happen to know where in the factory manual, which book and page preferably, the timing belt warning system is as my warning light intermitantly comes on and I have checked the timing belt tension and it is dead on, so if someone can point me where it is in the manual or even what to look under it would be much appreciated.
TIA
TIA
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From: Gone. On the Open Road
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From: Nova Scotia
If the problem is in the 'logic box' in the dash, I've no easy answer for you; however, the principle of operation is dead simple , and easy to check out.
There is a single wire comming from the tensioner, thru the TB cover, and on to the 'alarm' logic box . The alarm works on an approximate 3 min. delay(LC delay circuit?).
Confirming the TB tension to be OK, disconnect the wire at the TB cover (you may have to loosen the oil dip stick tube - one 10mm hex.), and take a short drive: the TB alarm should come in @~ 3 min. Everyone hold their water! - this is what's supposed to happen, and confirms the warning circuit to be functional.
Shut the eng. down (at your leisure), take a VOM/multimeter, and confirm <1 ohm (continuity) between the tensioner wire contact in the TB cover and chassis ground. Continuity should exist. If not, there is likely a 'dirty' contact within the push rod assembly in the front of the tensioner, or more likely, an abrasion/loose screw on the 4" wire between the carrier arm & TB cover contact. Reconnect the external wire.
All the alarm does is alert a prolongued loss of electrical ground thru the tensioner assembly. In static compression, the tensioner is solid steel from adjuster bolt to carrier arm - no hydraulic function whatsoever (the latter is a dynamic damping function, not one that establishes tension). The spring in the front on the tensioner serves to maintain a broken ground/continuity loss when the TB tension is too low . ie., if maintained for ~3 min., the TB lo tension alarm comes in. - plus the required change of underwear!!
Hopefully, the intermittant alarm is of the frayed wire/loose screw nature.
There is a single wire comming from the tensioner, thru the TB cover, and on to the 'alarm' logic box . The alarm works on an approximate 3 min. delay(LC delay circuit?).
Confirming the TB tension to be OK, disconnect the wire at the TB cover (you may have to loosen the oil dip stick tube - one 10mm hex.), and take a short drive: the TB alarm should come in @~ 3 min. Everyone hold their water! - this is what's supposed to happen, and confirms the warning circuit to be functional.
Shut the eng. down (at your leisure), take a VOM/multimeter, and confirm <1 ohm (continuity) between the tensioner wire contact in the TB cover and chassis ground. Continuity should exist. If not, there is likely a 'dirty' contact within the push rod assembly in the front of the tensioner, or more likely, an abrasion/loose screw on the 4" wire between the carrier arm & TB cover contact. Reconnect the external wire.
All the alarm does is alert a prolongued loss of electrical ground thru the tensioner assembly. In static compression, the tensioner is solid steel from adjuster bolt to carrier arm - no hydraulic function whatsoever (the latter is a dynamic damping function, not one that establishes tension). The spring in the front on the tensioner serves to maintain a broken ground/continuity loss when the TB tension is too low . ie., if maintained for ~3 min., the TB lo tension alarm comes in. - plus the required change of underwear!!
Hopefully, the intermittant alarm is of the frayed wire/loose screw nature.
