Questions and Answers

Volvo 850 ABS DTC 443 Q. Hi, I have an ABS fault on my 1996 Volvo 850, 2 litre, automatic transmission with 97,000 miles on the clock. The ABS diagnostic light came on the dashboard. My regular Volvo dealer told me I need to replace the ABS control unit and modulator costing about 2,000 Euro (2,298.47 USD).

A friend who had an ABS problem with his Landrover was quoted 3,500 Euro (4,022.28 USD) repairs but found a loose ground wire after obtaining the fault code and saved himself 3,500 Euro. I got the fault code from the Volvo diagnostic as 443 - pump failure. Initially, the fault light came on after ABS usage, ie it was mechanically activated.

This happened three times, now it is permanently lit. My assumption is that it is a mechanical fault with the pump. I presume the dealer checked that the relays and fuses are okay. Why can I not just get the pump replaced. It would be cheaper than both Pump and Control unit.

I don't know whom to trust since my regular service agent, who's quoting 2,000 for a new pump and control unit, never bothered to change the brake fluid. Are you familiar with this type of fault? Your advice would be greatly appreciated.

Thanking you in advance,
Robert

A. Anti-lock brake systems are not something to be taken lightly. They are such a critical system to the safe operation of a vehicle that they should either be fully operational and certified or not working at all and the components removed from the vehicle. In your particular case you could get a second opinion on what is actually causing the fault, from either another dealership or an independent and reputable auto repair shop.

Even though you have a fault code that indicates that your pump is faulty it could be due to the control unit not reading the signals from the pump correctly, therefore the control unit could be the culprit.

I Recommend you take your vehicle to another reputable, certified repair shop for a second opinion. It could be just as likely a wiring problem as a bad pump. And you can replace just the pump. Sounds like he wants to cover himself with the control unit.