Porsche Cayenne 92A Hybrid brake vacuum issue

CASE STUDY: Opus IVS supports a customer with a Porsche Cayenne 92A Hybrid brake vacuum issue.

IVS 360, from Opus IVS, provides diagnostics and live repair guidance support services to help workshop technicians fix complex vehicles safely and fast. All Opus IVS mechanical repair solutions come with live repair guidance from IVS 360 OEM brand-specific master technicians.

Using the DrivePro’s diagnostic software and extensive product knowledge, the IVS 360 team identifies the cause and steps needed to fix vehicle faults. Support from the team can be requested directly from a DrivePro device or DrivePro Elite Diagnostic Kit.

Opus IVS’ experts remote in real time directly to vehicle communication systems to diagnose, program and calibrate vehicles. This eliminates the uncertainty, giving workshops the confidence to get the most complex vehicles back on the road safely and fast.

A recent case involved a Porsche Cayenne 92A 2011 model year. The vehicle had a hard brake pedal, which indicated a fault with the electrical vacuum when switching to Hybrid Drive. The IVS 360 team supported the customer with the following advice:

Make: Porsche

Model/Yr: Cayenne (2011 – 2017) Hybrid

Symptoms: Hard brake pedal

Example picture of Cayenne engine bay relay board.

The brake servo has a mechanical and electrical vacuum pump to create the required vacuum for the brake servo. When the vehicle switches to hybrid drive the electrical vacuum pump is used, or at a time the mechanical pump does not make required vacuum when the engine is running.

Fault codes: P147900 Brake boost vacuum system, mechanical failure DME – ENGINE ECU

The repair:

1. Connect your diagnostic tool and read out the fault codes

2. Checking the vacuum of the mechanical pump:

3. Check the vacuum pipes

The vacuum lines contain check valves, so be sure these are working. Check the vacuum lines for micro cracks. There are other vacuum systems for the control of the Secondary Air injection, intake manifold flaps. The solenoids (2 for Air injection, 1 for inlet manifold flaps) are mounted at the rear of the engine on a bracket. There is another vacuum line and solenoid for the engine coolant pump (water pump) shutoff slide control at the front of the engine.

4. The electric vacuum pump

The electrical pump is mounted lower on the engines side, near the front of Bank 1. The electrical pump is powered via a relay (3) in the under-bonnet fuse board, maxi fuse (4) provides the pump protection, the DME switches the relay depending on the pressure sensor reading. The pressure sensor is mounted in the vacuum line near to the brake servo.

5. Test the electrical vacuum pump

Check that the electrical vacuum pump runs and will create the required vacuum. Do this with engine off key on, the relay can be worked from the DME drive link function (or bridge relay) The DME only monitors the control of the relay not the pump electrical function.

6. Replace the electrical pump

If the electrical pump is determined to be faulty, i.e. not running (fuse and relay ok) noisy during operation, or is getting hot quickly, replace the electrical pump always together with the relay (3) and maxi fuse (4).

Tools required:

• Diagnostic tool

• Hand vacuum pump

• Smoke tester (optional)

For more information on Opus IVS diagnostic solutions and IVS 360, please visit www.opusivs-uk.com.

T: +44 (0) 1865 870 060 E: sales-uk@opusivs.com

Opus IVS 360 Case Study

Opus IVS 360 OEM-trained Master Technicians help a customer with a BMW fitted with a M57TU engine and automatic transmission, suffering from a blocked DPF.

The Opus IVS team provide live repair guidance to workshops globally. The team helps technicians establish the fastest, most reliable, and accurate diagnosis, and take them through the process step-by-step, all the way through to vehicle repair. Ultimately, workshops have access to a team of ‘behind the scenes’ OEM brand-specific technicians that they can rely on daily to provide the actual fix.

The IVS 360 team often see multiple cases of the same nature. This is particularly true of BMW vehicles fitted with the M57TU engine and automatic transmission, which results in a blocked DPF.


• DPF will not regenerate


• Engine over-cooling, even after fitting main and EGR thermostats

The Fix

• Retrofit an additional thermostat

BMW cars fitted with the M57TU engine and automatic transmission often suffer from a blocked DPF. Here’s a typical scenario:

Diagnosis has been carried out and during a test drive you have noticed that the engine fails to reach over 68 oC (approximate). When left to idle, the engine temperature can be seen to increase. This indicates a thermostat is sticking open. The normal repair of replacing the main engine cooling thermostat and EGR cooler thermostat has been carried out and a test drive has been undertaken to test the operation of the cooling system. However, once again, the engine temperature fails to exceed 68 oC (approximate).

The cause can be the automatic transmission oil cooler thermostat stuck open. A test to prove this would be to clamp off the pipe between the cooling system and the automatic transmission oil cooler then repeating the test drive. The automatic transmission oil cooler thermostat is not available separately from the cooler, however there is a work around. You can purchase an inline thermostat that is available from the VAG group or many of the main aftermarket parts retailers, Part number 4e0121113.

For more information about IVS 360 and how it can support your workshop, visit www.opusivs-uk.com.

Opus IVS helps independent automotive workshops repair the most complex vehicles fast with diagnostics, programming and live repair guidance from OE brand-specific master technicians. As vehicles become technologically advanced, we enable independent automotive workshops to get them back on the road safely. Powered by Autologic, Opus IVS is committed to helping workshops complete repairs with intelligent vehicle support today, for a safer world tomorrow.

Email: sales-uk@opusivs.com

Case study: Faulty start-stop

Opus IVS 360 Master Technicians help a customer with a Mercedes-Benz, which has an inoperative ECO start-stop function

Opus IVS delivers beyond the scope of general scan tool diagnostic capabilities. Their IVS 360 Live Repair Guidance support service gives workshops access to the IVS 360 team of OEM experienced, factory-trained diagnostic technicians. Not only does the team help establish the fastest, most reliable, and accurate diagnosis, they actually take you through the process step-by-step, all the way through to the repair. Ultimately, workshops have access to a team of behind the scenes OEM brand-specific technicians that they can rely on daily to provide the actual fix.

Customers can access the IVS 360 team directly from their Opus IVS diagnostic devices. Using the diagnostic software from DrivePro, Autocom, Autoenginuity and extensive product knowledge, the team identifies the cause and steps needed to fix vehicle faults, helping technicians repair the most complex vehicles fast with live repair guidance.

Here is the latest case from the IVS 360 Mercedes-Benz team:

Make: Mercedes-Benz

Model: Mercedes-Benz A class (W176), B class (W246), CLA (W117) and GLA (W156) class vehicles from 2009-2015 up to 2019

Fault: Direct Starting/ECO start-stop inoperative

Fault code: B21059A current & stored in Drivers SAM (Signal Acquisition Module)


Possible causes:

  1. The charge level of starter battery is staying frequently between 55 <> 65% (State of Charge) leading to insufficient battery power.

In the current climate due to the COVID-19 Pandemic, vehicles are not being driven often enough to bring the required charge level above 80%. This fault may be triggered if the battery is constantly below 55%.

2. Battery has aged. EFB type batteries that are aging prematurely are now being replaced with AGM batteries.

Repair steps:
Check the battery type, try to fully charge the battery with a smart charging battery station and re-test the battery.
“Confirmation of battery change” in the Drivers SAM under the ACTUATIONS menu should allow the fault to clear. Monitor and re-check the battery should the fault re-occur.

The Battery requires replacing.
Replace EFB wet battery with an AGM (Absorbent Glass Matt, also called Fleece) battery.

VeDoc requires amending, delete code 11O ~EFB battery installed.

Perform online SCN coding with Xentry Diagnostics / Pass-Thru or similar capable diagnostic equipment in the N10 (SAM) module. This will change the charging characteristics needed for the new AGM battery to operate correctly.

Confirm battery change in the N10 (SAM) under the ACTUATIONS menu.

For information on IVS 360 support, visit www.opusivs.com or email sales-uk@opusivs.com.
01865 870 060