Service Manual

Cold Starting Aid ISB, ISBe and QSB (Common Rail [...]
Page 10-30 Section 10 - Air Intake System - Group 10
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Charge-Air Piping (010-028)
Maintenance Check
Inspect the charge-air piping and hoses for leaks, holes,
cracks, or loose connections. Tighten the hose clamps if
necessary. Refer to the vehicle or equipment
manufacturer's specifications for the correct torque value.
Cold Starting Aid (010-029)
General Information
There are three types of cold starting aids used on ISB, ISB
e
, and QSB engines. They are cylindrical, brick, and
integral style. To gain access to the integral cold starting aid, the air intake manifold must be removed.
ISB CM850 preheat cycle information:
The intake air heater system is used to aid starting during cold temperatures. It energizes and de-energizes a heater
driver (which controls a high current relay) and the “Wait-To-Start” lamp. Use of this system prior to cold start is
termed as “preheat”. The amount of time necessary to turn on the intake air heater drivers during preheat is a function
of the intake manifold temperature at key on, as shown in Figure 1.
Figure 1: ISB CM850 and QSB CM850 Preheat Time in Seconds
ISB CM850 post-heat cycle information:
After a cold start, the grid heater can be activated during warm-up, which is termed “post-heat”. The post-heat
schedule is determined by the average of the intake manifold temperature at key on. Post-heat is deactivated at
vehicle speeds greater than 19 mph (30.5 kph). Post-heat operation parameters are listed in the Table 1.