TRACS/ABS: - TRACS pressure switch location? - Page 4

Chris_Rogers · Oct 9th, 2014, 09:55

I don't have a diagramof the internals of the hydraulic unit.

If the code is comming back immediately or won't reset then I'd suggest there is an open circuit as the switch should be normally closed.

I'd suggest you get a multimenter and check the resistance of the switch circuit between terminals 13 & 14 at the multiway connecter towards the hydraulic unit, the wiring diagrams should help you identify the terminals.

KBB · Oct 9th, 2014, 10:44

To confirm that you have the earlier system you will have located next to the ABS/TRACS modulator a large detachable combination relay. The DTC you have got (424) can also be down to a badly adjusted break pedal switch. The brake light should come on before the pressure switch in the modulator opens, if the pressure switch opens before the brake light comes on then DTC 424 will be set. If you can visually confirm you have the earlier system the are some very simple test procedures you can do with a DVM and a test light.

Cypher007 · Nov 17th, 2017, 09:38

ive got the dreaded 424 on my T5R. has anyone found out the fix or where it is so I can test it.

Nov 17th, 2017, 09:38	#33
Cypher007 Master Member Last Online: Jan 8th, 2024 14:20 Join Date: Dec 2001 Location: Lincolnshire	ive got the dreaded 424 on my T5R. has anyone found out the fix or where it is so I can test it. __________________ Volvo 854 T5R Yellow 1994 Aquamist 2D (Don & Aquamist) BMC panel filter (Don) Ferrita Cat Back (Don) Denso Iridium Spark Plugs (Hong Kong) PowerFlex Top Engine Mount (?) PowerFlex Wishbone Bushes (Elk Parts) 302mm front brake upgrade Goodridge front hoses (rears to be fitted later) 600W Inverter (ebay) History: 1991 Volvo 340DL (1982) 1994 Volvo 360GLE (1989) 1999 Volvo 360GLT (1988) 2002 Volvo 850GLT (1991) 2004 Volvo 850T5R (1994)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Oct 9th, 2014, 09:55	#31
Chris_Rogers VOC Member Last Online: Apr 10th, 2017 16:55 Join Date: Jan 1970 Location: South Kent Coast	I don't have a diagramof the internals of the hydraulic unit. If the code is comming back immediately or won't reset then I'd suggest there is an open circuit as the switch should be normally closed. I'd suggest you get a multimenter and check the resistance of the switch circuit between terminals 13 & 14 at the multiway connecter towards the hydraulic unit, the wiring diagrams should help you identify the terminals.

Oct 9th, 2014, 10:44	#32
KBB Master Tech Last Online: May 18th, 2020 10:57 Join Date: Dec 2006 Location: On Contract Dubai Automotve Technical Academy	To confirm that you have the earlier system you will have located next to the ABS/TRACS modulator a large detachable combination relay. The DTC you have got (424) can also be down to a badly adjusted break pedal switch. The brake light should come on before the pressure switch in the modulator opens, if the pressure switch opens before the brake light comes on then DTC 424 will be set. If you can visually confirm you have the earlier system the are some very simple test procedures you can do with a DVM and a test light.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)